Android email client, similar to Thunderbird

Question

I use Thunderbird as my Windows desktop email client. There is no Thunderbird for Android.

I actually quite like the Gmail client, but do not want Google reading all of my mail.

I need something which :

• will handle multiple accounts (at least a dozen), and keep them separate
• has good search capabilities (message body too, not just header) partial sender address, wildcard searches, date range searches, all of these combinable
• a bunch of plugins would be nice
• I especially want GPG support
• and I don't want it scanning my emails & using me as "the product"
• has IMAP support
• allows me to schedule how often it checks for new mail (not once an hour, like Gmail)
  • supports common mailbox formats, so that I could switch to a new client & import
• tags are nice
• mark as "in need of reply" & remind me

I don't need a calendar or fancy address book, but won't object. Low resource usage would be nice. Stable, with good support & an active user community.

Gratis (and add-free) would be great, but I am willing to pay, if there is a compelling reason. I don't need open source, but don't object to it.

Answer 1

K-9 mail is what I would personally suggest. I've not used it myself, but it's very popular among the open-source community because it's one of the few options on Android that properly supports plain-text email composition. In essence, it's a graphical version of the old text-based mutt email client specifically made for Android.

Of your various points:

• will handle multiple accounts (at least a dozen), and keep them separate: Pretty sure it properly supports multiple independent accounts.
• has good search capabilities (message body too, not just header) partial sender address, wildcard searches, date range searches, all of these combinable: Not sure about search abilities.
• a bunch of plugins would be nice: I don't think it provides plugins, but I've heard it natively provides a vast majority of the features that most people would want plugins for.
• I especially want GPG support: Provides native OpenPGP support
• and I don't want it scanning my emails & using me as "the product": It's FOSS made by the community, so not likely to be an issue.
• has IMAP support: Yep (though it's rare to find an otherwise decent email client that doesn't these days)
• allows me to schedule how often it checks for new mail (not once an hour, like Gmail): Yes, although I don't remember what granularity it provides for this.
• supports common mailbox formats, so that I could switch to a new client & import: I don't know if it fits this one or not, but if you're actually using IMAP as it was intended to be used, you shouldn't need this (because you should have copies of everything on the server).
• tags are nice: Not sure about this one, but you can emulate tagging by storing multiple copies of each message, one each in a folder that represents the tag.
• mark as "in need of reply" & remind me: I actually don't know of any email client that does this, and I don't think K-9 can either, but I'm not sure.