Knitamus now supports data syncing through your iCloud account, which is good if you'd like to be able to use Knitamus on more than one device. To turn sync on, visit the Settings tab of the app and flip the switch!
The Inside Story
The iCloud system will, I think, be more reliable than Dropbox (which is what Knitamus used until the service ended) and, I hope, use less of your battery and bandwidth. It requires more work from the app, though. Especially for lists of things, like the list of chart positions you've saved for a project, Dropbox automatically handled situations where you'd added a position on your phone and deleted one from your iPad. With iCloud, Knitamus has to handle conflicts like that on its own.
When you add in syncing your project list with Ravelry (a feature I wouldn't want to be without!), things get complicated quickly.
Since duplicate data is annoying but lost data is terrifying, I've tried to err on the side of keeping more than you might want rather than deleting more than you might want. If you notice any problems, please let me know! Your input helps me make continuous improvements. :)
If you are syncing with CloudKit and with Ravelry, you may find it difficult to delete projects. I'm working out a solution for this, but for now if you need to delete a project, I would suggest deleting the project from the Ravelry website, then putting your device in airplane mode before opening Knitamus and deleting the project there. You'll probably need to do this on every device that has the project.
You may find that you sometimes get an extra empty project. I think this is also related to using iCloud sync and Ravelry sync at the same time. I'm looking into this problem as well. :)