Very buggy, would not recommend. – Picup Review

The app crashes mid-upload. The file that was being uploaded may or may not be available after the crash in the history list to retry. The process for selecting multiple photos to upload is cumbersome and takes more taps and repetitive screens than necessary. Multiple photos can't be grouped in an album - you can only get individual links to the photos. The app does not support imgur accounts - only anonymous uploads are supported (or at least it is not evident how to sign in with your own imgur account). There is a fancy animation of the upload process that adds no value to the upload itself - one wishes that the developer dogfooded the app and ironed out the bugs instead of focussing on eye candy.
Review by Shashvat Sinha on Picup.