In general, I would prefer using the app over the browser interface, because the phone is more convenient to use than a computer. I also believe I am able to achieve better retention in the app. However, there are issues that more or less force me to use the browser:
- The new, more flexible review settings are not used in the app (I can not mark a fully mastered sentence as easy or hard).
- There is still no way to make new clozes out of existing ones.
- There is still no direct link to the source sentence at Tatoeba.
- There is no integration with the forums.
If I used the app more, I could probably come up with more issues, but how about resolving these ones first?