If you have Roundcube webmail access, this app is for you. You do not have to use the browser on your maybe too small screen. Roundcube skins are usually not optimized for handheld devices and touchscreens, this app however is. You still can have all the advantages of Roundcube though, no need to know about POP3/IMAP and SMTP protocols, so you can send and receive emails right away. Multiple identities with different signatures and multiple accounts are supported.
If you meet a problem, please use the Send Application Log menu to send a report after the problem. If your webmail interface is not Roundcube, then this application will not work! If you provide the correct URL (e.g. https://someserver.org/roundcube/) user credentials and this URL is indeed a Roundcube interface, then the app should work fine. A number of cPanel fronts are also supported.