Mail.Ru – Email App. Set a time to receive notification, select services, folders or create a personal filter to receive only those alerts that are important! – Caching emails. Emails are stored in the phone’s memory and are available without a network connection. Read messages and view attachments in transport or, for example, in the countryside.

: https://play.google.com/store/apps/details?id=ru.mail.mailapp&hl=en_US