Email client with support for multiple accounts and From addresses

Question

I’m looking for an email client (IMAP) for Android, which supports

• multiple accounts, and
• multiple From addresses per account (aka. identities, aliases).

When composing a new email, it must be possible to choose a From address. It would be great if there is no default, so the user has to make a choice.

When answering an email, the client should automatically choose the From address the original email was sent to. But it should also be possible to change the From address manually.

Gratis is required, FLOSS would be great.

Answer 1

I'd recommend you K-9 Mail, available for free at Google Play, Aptoide, and F-Droid (which shows it's FOSS):

• Supports multiple accounts: Yes (I'm using it with 3 different accounts currently)
• Multiple "From" addresses per account: Yes, it's called "Aliases". I didn't use that yet on K-9, so I cannot tell how well it works concerning "no default" and "auto-select"
• IMAP support: Yes, with the choice of Push & Pull (IMAP Idle versus Poll) (all my accounts are using that), POP3 as well (just in case)
• Gratis, FOSS: Yes, yes

^{K-9 Mail: Account overview, Folder view (source: Google Play; click images for larger variants)}

These two screenshots nicely demonstrate the features you requested (well, most of them): Multiple accounts (first screenshot), and even a "unified inbox" for all of them ("virtual"; you can assign colors to your accounts to distinguish them here).

For alternatives, be welcome to my list of Email Apps, where you can also find reviews, video demos, and more linked to the apps. And a ton of addons/widgets/… for K-9 Mail as well.

Answer 2

AquaMail also supports multiple accounts and multiple aliases.

Not to mention it exists for many years and has plethora of other features.