K-9 Mail is an open source email client that works with basically all email providers.
+ supports multiple accounts
+ Unified inbox
+ privacy friendly (no tracking at all, just connects to your email provider)
+ automatic background synchronization or push notifications
+ local and server-side search
+ OpenPGP email encryption (PGP/MIME)

Supported Android
(4.1 and up)
Ice Cream Sandwich (4.0 – 4.0.4),Jelly Bean (4.1 – 4.3.1),KitKat (4.4 – 4.4.4),Lollipop (5.0 – 5.1.1),Marshmallow (6.0 – 6.0.1),Nougat (7.0 – 7.1.1),Oreo (8.0 – 8.1), Pie(9.0), Android 10, Android 11

Download K-9 Mail 5.914 APK Beta

k9-5.914.apk

k9-5.913.apk