Work · alternatives · 2026

24 alternatives to Protocol66

66-day habit challenge. Miss a day, start over.

Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes.

1
Streaks66▲218
Daily habits tracker with AI
2024 · apps.apple.com · its alternatives →
2
21 Days Challenge▲96
A set of challenges to be accomplished every day for 21 days
2019 · play.google.com · its alternatives →
3
Rabbit Habit Tracker▲114
A minimalistic habit tracker with a powerful iOS14 widgets
2021 · its alternatives →
4
22 Days▲105
Start to effectively control your habits
2019 · apps.apple.com · its alternatives →
5
100-Day Habit Tracker▲121
Build long-lasting habits with the 100 day habit challenge
2023 · systemsumo.gumroad.com · its alternatives →
6
TwentyOne▲108
Build habits in manageable bites, together
2023 · apps.apple.com · its alternatives →
7
#90DaysOfProse▲181
Make writing a habit
2021 · its alternatives →
8
21 Days Habit Tracker▲106
Establish the foundation of success - a one simple habit
2023 · missdigitalplanner.gumroad.com · its alternatives →
9
Fast Habit Print▲160
Print a page. Track your habit. Free and simple.
2019 · its alternatives →
10
Law of 100▲194
Make or break a habit in 100 days.
2022 · its alternatives →
11
21 Habits▲8
Challenge yourself for 21 days
2024 · its alternatives →
12
Make It A Habit▲79
Set a habit and a price. If you fail, you pay.
2019 · its alternatives →
13
Habit Challenge▲101
Form new habits and keep your life on track
2018 · apps.apple.com · its alternatives →
14
Habitz ▲96
Goal planner & progress
Jan 2026 · apps.apple.com · its alternatives →
15
Squad▲166
Group accountability for positive habits
2023 · joinsquad.co · its alternatives →
16
HabitPilot:90 Days Challenge▲3
AI assisted 90 days cycle based habit tracking app
May 2026 · apps.apple.com · its alternatives →
17
66-Day Streak▲2
A focused habit tracker built around the 66-day habit model
Mar 2026 · 66streaks.com · its alternatives →
18
That's It, I Quit!▲96
Break any bad habit in 21 days starting today, not someday
2023 · memesthatpay.com · its alternatives →
19
mostly▲6
A habit tracker that doesn't punish you for resting
Apr 2026 · getmostly.app · its alternatives →
20
Habit Tracker To-Do▲63
Build better habits & track progress
2023 · its alternatives →
21
21 Days Habit Tracker▲8
A Notion template to build new habits
2023 · sidgangs.gumroad.com · its alternatives →
22
21 Days Challenge▲3
A set of challenges to be accomplished every day for 21 days
2020 · 21dayschallengeapp.com · its alternatives →
23
21Days: Build Habits▲12
Build habits in 21 days
2025 · apps.apple.com · its alternatives →
24
a habit▲6
I kept failing at habit apps. I'd add 6 habits, miss a day, feel guilty, stop opening the app entirely. So I built the opposite: an app that only lets you track one habit at a time. The idea is that one habit done beats ten habits planned. Pick one thing, show up daily, and only move on when it's automatic. It's free with ads. Would love your feedback on whether this constraint feels liberating or limiting. iOS: https://apps.apple.com/app/id1549454193 Android: https://play.google.com/store/apps/details?id=com.davvie.hab...
Jan 2026 · ahabit.app · its alternatives →

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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →