EBSCOhost is optimised for mobile devices so a mobile app is not required, (however, apps are also available).
This link provides direct access to the EBSCOHost mobile responsive page. Choose which databases to search, then limit and sort results. Get full text results in HTML/PDF, save and email for later offline access.

Optimised for mobile devices so there are no apps to download or install. You will need to log in with your University ID and password via institutional log-in if off campus.

With JSTOR you can email citations to yourself to read articles later.
​JSTOR’s interface automatically adapts to the screen size of a device without requiring a separate mobile URL or any device configuration. Just go directly to www.jstor.org on a smartphone or tablet, and the screen will adjust accordingly!