A lot of teams and companies use Basecamp to track projects (we use it here at Android Police even), and today there's a new version of Basecamp. Basecamp 3 is a complete revamp of the service, and there's an Android app to go along with it.
If you've been using Basecamp for your own project or as a part of a team, you'll need to make a new Basecamp 3 project. There's currently no migration tool, and your old Basecamp 2 projects won't be accessible from the BC3 app. There are a ton of new features in Basecamp 3, as well as a new interface. You can assign multiple people to a to-do, generate reports, share a subset of information with clients, and more.
The Android app has support for all the new Basecamp 3 features and apparently has full Marshmallow compatibility. The Basecamp 2 app is still available in the store as well. Basecamp is free for basic use, and the new Basecamp 3 plans for teams no longer have limits on how many projects you can operate. You just get more features when you pay for more expensive tiers.
- Basecamp 3