Over the last decade, the idea that building good habits—or breaking bad habits—is one of the keys to a happier, healthier, longer life has gone mainstream. Books like Atomic Habits by James Clear and Tiny Habits by BJ Fogg argue that the sum of many small daily behaviors—like going for a walk or brushing your teeth—is far more important than the occasional dramatic gesture—like flogging yourself through a five-mile run you haven't trained for or flossing the night before visiting the dentist.

But building new habits isn't always easy. If it was, everyone would brush their teeth twice a day, get in their minimum recommended 150 minutes of moderate-intensity cardio and two strength training sessions each week, and never miss a work deadline. 

While you'll have to read one of the above books if you want a proper deep dive into habit building, it's long been recognized that one of the most powerful ways to build new habits is to track when you do them. If you don't keep yourself accountable in some way, you're almost certain to fail.

And while you can use a wall calendar or a journal to record your habits, an app can be a more convenient solution. Unless spending too much time staring at screens is the habit you're trying to break, you probably always have your smartphone with you. It can remind you if you haven't done something yet that day, and there's more room for nuance in how often you have to perform a particular habit. A habit tracker app can also automatically track other things, like your activity goals.

There are lots of different apps that offer some kind of habit tracking. Most are based around building a daily streak or not breaking a chain of X's on a calendar, although they generally also allow you to set a target number of days per week or per month rather than just forcing you to do every habit every day. I considered, researched, and tested almost 40 apps for this article—and here are the five best habit trackers.

The best habit tracker apps

• Streaks for iPhone users

• HabitNow for Android users

• Way of Life for gathering lots of data about your habits

• Habitify for planning your day around your habits

• Habitica for people who want to turn building habits into a game

What makes the best habit tracking app?

Habit tracking is an inherently simple idea. Did you do the habit you were trying to build today? If yes, check a box. If no, don't check a box (and question why you weren't able to check the box). It's easy to see why a wall calendar or a little notebook and a red pen were the default options for so long.

This simplicity, though, means there are a massive number of apps that claim to be capable of tracking habits while being really awful to use. For this list, I set the bar really high. For a habit app to be great (and to beat out a wall calendar), it has to:

• Have a mobile app at a minimum. A desktop app or a website that syncs is an unasked-for bonus, but a smartphone app is a must. It's the only device you can always rely on having on hand, which means you can mark off habits as soon as you do them. Brush your teeth in the morning? Let's be honest—your phone is already with you in the bathroom, so you can check it off right there and then.

• Allow for flexible habit tracking. The big advantage of using a mobile app is that you can track things in more nuanced ways than with a calendar. The best apps should let you set a target number of times per week or per month, track habits you are trying to break, and otherwise offer a lot more control over how you track what you want to do and when. 

• Be under active development. Since habit tracking apps are so simple, there are a lot of unmaintained apps out there that seem to have been built by developers as a side project or just for fun. Habit tracking is a long-term plan, so I only included apps that were still actively supported and had been updated in roughly the last year—that way, you can be sure they'll work for the next few years, at least. There's nothing worse than getting stuck with an outdated app you love as it slowly stops working properly.

• Be quick, intuitive, and easy to use. Tracking your habits should be simple and take no more than a few seconds. If it's awkward, it won't fit into the good routines you're trying to build. Any app that adds friction to the process didn't make this list.

• Offer stats, streaks, and data. If you're going to use a smartphone app, you might as well get the benefit of instant data analysis. All the best habit apps offer statistics that break down things like how often you do each habit, how long your current streak is, and more.

I've been writing about self-improvement, building habits, and apps for almost a decade—and I even have a BSc. in Psychology. If there's an approach to tracking habits out there, I've probably tried it. Although I love analog tools, I genuinely think that a well-designed app offers the best balance between simplicity and effectiveness. I use one of the apps on this list myself, though I would happily use the other four if I needed to (or changed smartphone platform). 

To test the apps on this list—and a whole lot of the ones that aren't—I signed up for whatever free account or trial was available. Then, I added a few habits and used them over a few days to see how nice they were to use, explore any quirks, and look at their claimed features. After all, the habit tracking mechanics side of things is simple—it's building a nice app that's the real challenge. (I've been updating this list for three years and covered habit tracking for other publications in the past, so I've tried all of these apps at least a couple of times.) From that and relying on my experience with similar apps, I was able to cut the list down to just five great habit tracking apps.

The best habit trackers at a glance

Best habit tracker app for iPhone

Streaks (iOS, Apple Watch, macOS)

Streaks pros:

• A great Apple-focused habit tracking app

• Super fast and easy to use

Streaks cons:

• The design might not be for everyone

Streaks is the standout habit tracking app for iPhone users (and the one I use any time I'm trying to build a new habit). It's super simple and quick to use, while offering enough options for tracking any kind of habit. Given the name, it's somewhat obviously based around the idea of building and maintaining a habit streak—though it's flexible enough for almost anything.

Streaks enables you to track daily, weekly, and monthly habits with a single tap. You can set it so habits have to be done a certain number of days per week or per month, on specific days of the week, or recurring every few days. You can also set it so you have to mark the habit off multiple times per day, like, say, brushing your teeth twice.

Streaks plays really nice on Apple devices. There's an iPhone, Mac, and even Apple Watch app so you can keep track of things wherever you are—and your habits sync between them using iCloud. It also integrates with Apple's Health Kit, which means you can set habits that are automatically marked off by the data collected by your iPhone or Apple Watch, like walking a certain number of steps, sleeping a set number of hours, or working out for at least an hour each day. On top of all that, there are Home Screen widgets. 

For such a simple habit app, Streaks also offers surprisingly good statistics about your habit streaks. Tap the star icon in the bottom-right corner, and you'll see an overview of all your streaks, how often you've completed them, on what days, and at what time. You can then tap on any of the task icons to see an individual breakdown of the same data. Similarly, the recently added note taking is surprisingly robust. It won't replace your journal, but it can add context to your habit tracking. 

Once you're set up, checking off a habit in Streaks takes two taps: one to open the app, and another long tap on a habit to mark it as done. That is, of course, if your iPhone hasn't already checked it off for you.

Streaks price: $4.99 for the universal app.

The best habit tracker app for Android

HabitNow (Android)

HabitNow pros:

• A really great Android habit tracking app

• Free plan is sufficient for most people

HabitNow cons:

• Built-in task tracking is pretty basic

HabitNow is a great, good-looking habit tracker for Android users. The free plan allows you to track up to seven habits, which is more than enough for most people. If you want to track more, Premium requires a one-off payment of $9.99.

With HabitNow, you can track daily, weekly, and monthly habits, as well as add recurring tasks (which aren't tracked) and single tasks (one-off to-dos). You can set what days you want each habit to repeat on, if you want to be reminded to do it, and whether you want to mark it off by ticking yes or no, by recording a numeric value, or by running the built-in timer for a certain period of time. (If you have the Premium plan, you can also set a checklist of sub-tasks that have to be done.)

While HabitNow's to-do list functions are basic, its habit tracking is as good as anything available on iOS. If you want to add a reminder to buy a new book or do something else related to your greater habit-building goals, it can be useful to have everything all in one app. Otherwise, I'd suggest focusing mostly on the habit tracking side of things. 

HabitNow offers all the stats you could want. In the Habits tab, you can see your current streak, completion rate, and your completions over the last week. Tap either the Calendar or the Statistics icon for a more detailed rundown of how you've done over a longer time frame. 

HabitNow price: Free habit tracker app for up to 7 habits; $9.99 for Premium with unlimited habit tracking and more features. 

Best habit tracker app for gathering lots of data

Way of Life (iOS, Android)

Way of Life pros:

• All the data a nerd could ever need

• Affordable one-off pricing

Way of life cons:

• Not the most intuitive app to use

Most habit tracking apps are pretty binary: either you do the habit and keep your streak going, or you don't do the habit and break your streak. While this can be great for forming new habits, it can be a little too strict for some things. This is where Way of Life comes in.

In Way of Life, each habit gets its own journal. On any day, a habit can be marked as done, not done, or skipped (which doesn't break any streak). You can also add a note explaining, say, why you broke a habit or what workout you did. This way, you can build up a much better picture of what habits you're sticking to, and when and why you're not doing them—all of which can be explored in the Trends tab. 

Way of Life also has an interesting approach to streaks (it calls them "chains"). You can try to build the longest streak possible, but you can also set custom target streak lengths by tapping on Chains when setting up a journal. This means you can try not to drink soda for five days straight or meditate for three days in a row, and then take an allowed break. It's a much more realistic approach for many people, and is less likely to crush your motivation if you miss a day or two.

There are also "red chains," which record bad runs of days where you keep failing to do your new habit. I'm not sure how motivating this particular framing of things is, but some people may like the reminder—and be prompted to break the red chain with a green day.

Way of Life price: Free habit tracker for three habits; $6 for Premium with unlimited habit tracking and cloud backup. 

Best habit tracker app for organizing your life

Habitify (iOS, Android, macOS, Web)

Habitify pros:

• One of the best cross-platform habit tracking apps around

• Integration with other apps allows for automatic habit tracking

Habitify cons:

• Subscription price is very expensive for a habit tracking app

Habitify is one of the slickest habit tracking apps out there, and it's great that it's available on iOS, macOS, Android, and the web—but it is one of the few apps on this list that requires an ongoing subscription to get the most from it. If $4.99/month, $34.99/year, or $64.99 for lifetime access is going to be a dealbreaker, you're better off with one of the other apps.

If an ongoing subscription isn't an issue for you, Habitify has a lot to offer. One of its best features is the ability to sort your habits into habit areas. The defaults are Morning, Afternoon, and Evening, but you can also create your own like "Mindfulness" or "In the Gym" and assign new habits to them. This way, you can easily group related habits, so your screen isn't cluttered with all the things you're trying to keep on top of. 

Habitify also enables you to attach to-do items to an "Action List" for each habit. If you need a reminder to grab your gym gear, for example, it's a handy feature. It can also track your mood (via emoji) and details about how your habits are going (via notes).

If you can convince your friends to use it (or are prepared to compete against strangers), Habitify also offers social Challenges. You can join an existing one—like hold a plank for 2 minutes or drink 1.5 liters of water every day—or host your own. It's an interesting way of motivating yourself to stick with a new habit.

And, of course, Habitify has the usual streak tracking and data viewing features you'd expect from any good habit tracking app. You can see how you're doing in general, or drill into any specific habit, in the Progress tab. 

But perhaps the most interesting feature Habitify offers is its integrations. It can sync data with Apple Health and Google Fit so that habits are automatically marked off. There's also an API, and it can even connect to thousands of other apps using Zapier. That way, you can do things like automatically check off habits when you complete a task in your to-do list. For some people, that might just be worth the ongoing subscription.

Habitify price: Free for 15 check-ins per week; from $4.99/month for Premium with unlimited habit check-ins, unlimited skips, data export, and other major features. 

Best habit tracker app for people who want to turn building habits into a game

Habitica (iOS, Android, Web)

Habitica pros:

• The RPG conceit successfully gamifies habit building

• Essentially free to use

Habitica cons:

• RPG elements make the app a lot harder to use for simple habit tracking

Habitica (formerly HabitRPG) is a totally different take on habit building. Instead of trying to build a streak or carefully record how your life goes, it turns the whole process into an RPG. You can add tasks, daily activities, and habits to a list—but you can also battle monsters with your friends. 

When you sign up for Habitica, you create a character. As you complete your tasks and habits, you gain experience points and gold, so you can level up or buy cool gear. Once you reach level 10, you can choose whether you want to be a Warrior, Rogue, Healer, or Mage. So far, so Dungeons and Dragons. 

While Habitica is far and away the hardest habit tracker on this list to use, it's also kind of fun—at least if a pseudo-retro gamified experience appeals to you. It's especially motivating if you get your friends to use it too. You can all form a party, go on quests, and fight bosses. If one of you fails to complete your daily tasks, all the rest of the party can take damage. If your friends shouting at you for letting them down doesn't prompt you to read a book (or at least pretend you did), nothing will. 

Of course, this gamification comes with its downsides. If you're a data nerd, you'll be disappointed that stats in Habitica have more to do with health and mana than they do with your task completion rate. And there are, of course, two in-game currencies: gold, which you get for completing quests and doing tasks, and gems, which you have to buy with actual money or get through competing in challenges. Still, neither really takes away from using Habitica to build habits; both problems are just normal parts of the RPG-style package.  

Habitica price: Free plan with most features; from $4.99/month for bonus items, the ability to buy gems with gold, and more.

Use a habit tracker to build habits that last

While it's easy to get caught up hyper-focusing on different productivity tools, to build new habits, you have to actually go out and do them. All the apps on this list are incredibly useful if you want to motivate yourself to keep learning French or going to the gym, but you still have to open Duolingo or lift the weights. If none of these apps are keeping you honest, check out stickK—it's an accountability service where you put real money on the line. If the thought of donating to Save the Whales makes you sick, it might be just the tool to help you build the habits you want. 

Related reading:

• The best AI productivity tools

• 12 morning and evening routines that will set up each day for success

• How to rebuild your work habits from scratch