The 100 mistakes working developers make most often.
Tick them off in the checklist, then make them truly your own through reflection.
Key features
Knowing the mistakes is only the start. Reflection is how you make the lessons your own.
From writing code to working in a team, the mistakes that keep recurring in real workplaces, organised by category.
Answer the reflection questions prepared for each mistake and build real understanding rather than rote memory.
See your progress by category and overall at a glance, and feel yourself growing.
Use the same data on iPhone, iPad and Mac. It syncs automatically through CloudKit.
Bookmark the items you want to see again and revise them together later.
Thanks to Mac Catalyst, the iPhone app runs on your Mac just as it is. Study wherever you are.
10 categories
Sorted by the situations junior developers actually run into.
Plans
Try the first 30 for free, then unlock all 100 with PRO.
Free
Free
Free for good
PRO Monthly
Monthly
Price shown in the App Store
PRO Lifetime
Lifetime
Pay once, keep it for good
Multi-platform
With iCloud sync built on CloudKit, you can pick up on any device, wherever you started.
30 free, and all 100 with PRO.
Become a developer who doesn't make the same mistake twice.