I need to set up my business email*(non gmail email)* on the mobile devices (Nexus 5 and Nexus7). The business has its own private mail server. The way I can do it is by using Gmail app on these devices. The question I have is does Gmail app on the mobile devices store the IMAP emails(non gmail emails) on the gmail servers? Or Gmail app is just a client and does not bother storing the IMAP emails(non gmail emails) on its servers that are not gmail emails? Thanks for the insight...
The gmail app is just a client and nothing is stored on Google's servers. The use of IMAP simply means that the email is stored on your company's servers and your phone, as compared to the older POP where the email is pushed to your phone and deleted from the server.
The emails might show up "mixed" if you show all inboxes but you may be rest assured that they do not reside on Google's servers.