Use APKPure App
Get Save my Attach old version APK for Android
Kaufe bei Google Play im Web. Dein Einkauf steht dir sofort auf deinem Android-Gerät zur Verfügung – ganz ohne lästiges Synchronisieren.
Save the GMail attachments to the SD-card. Tap on "Preview" button in the GMail and select "Save ..." from the list.
Works with Email app also (use "Open").
Please note: this app doesn't have a launch icon! You could open it only from your GMail app by tapping a "Preview" button