There are currently a few specific functions that hardly work on a mobile phone screen:
➀ Search field not visible/accessible in the mobile browser (Android, Firefox)
➁ Adding collections for new artifacts: update button not visible in portrait format
The question here is whether you only fix the most necessary things now and focus on an Android app in the future OR rather go in the direction of responsive design?
(Irrespective of this, I would definitely offer the Android app for sharing as planned. This function can (presumably) not be replaced by a responsive website and is also one of the most important features for me to save information on the go
In addition to an app that makes it possible to share content with Collecta from the mobile phone, a usable search on the mobile phone would be the second most important feature for me.)