I’m delighted to see a recent update to this app, as it indicates it has not been abandoned. As a research oriented medical director I spent a good deal of my time reading scientific PDFs and annotating these for future reference or citation. Although this is not the most intuitive program to set up, it does synch beautifully with Zotero and is an excellent annotation app. Moreover, one can easily export annotations by using the share icon (box with upfacing arrow) and using email command. This appears to be an undocumented feature - and I have no idea why it works this way-but it does so beautifully. Would greatly benefit from some instructional videos as many features hidden, and again not intuitive. Due to Zotero synch has largely replaced most of PDF readers, e.g. Goodreader. Once you have figured out the kinks and qwerks your efforts will be well rewarded. By all means also implement Zotfile on Zotero.

Apple should not let people pay for the in-app features because they DO NOT WORK. The app itself seems well-designed and intuitive. You can sync it with your Zotero library to view any PDF you have in Zotero. But to do any kind of markup on the PDFs, you have to pay for the Annotations pack. The app lets you preview the functionality of the paid features but it’s not a true trial — you get to play around annotating a sample PDF within the app but can’t test syncing the annotations with your own Zotero account. I liked the features (and didn’t see the purpose of a read-only PDF viewer that synced with Zotero) so I paid for the Annotations pack right away. The annotations I made to PDFs within the Papership app never showed up in Zotero. It just never worked at all. It was supposed to be automatic and seamless. But it doesn’t work and there is zero support from the developer. I later found lots of similar complaints going back several years on forums. I can’t believe Apple still lets this app sell features that are completely nonfunctional. Save yourself the headache and $10 by using the Zotfile plugin and a PDF reader of your choice until Zotero finally releases its iOS app.

Being able to sync my Zotero library on to my iPad and annotating the PDFs is something I’ve used extensively over the years. No other app has been able to accomplish this, to my knowledge. That said, PaperShip isn’t perfect. Mainly:* While you can search for literature in the app, I have never been able to add it to my library successfully. It usually just silently fails. I still have to add items to my Zotero library on my regular computer, then sync them to the iPad. Please, please fix this. It’s a hassle and it would be amazing to do everything directly from the iPad.* Minor feature suggestion: a built-in “dark”/inverted mode for PDFs would be nice. You can use the iPad OS smart invert to do this, but having it in the app would be nice.

I have been using this app for over 3 years with iPad and mac. One of the greatest features of this application is that the developer doesn’t limit platforms, though the mac version is on sale. So, I can install this iPad app on my Apple silicon mac without additional payment.I had a trouble with restoring annotation function when I updated my iPad to 13 inch. It looks like the purchase linked with the country where you buy this pack. If you have multiple apple IDs, you have to uninstall it once and change your country where you bought, install and restore the function again. I can see some customers had the same trouble. I hope this could help them.