Change the size of your Sender Avatar or go for a classic check boxes view by removing it altogether.
- Tap the SideMenu icon at the left of your navigation bar to open the Side Menu.
- Tap the Gear icon at the bottom of the Side Menu to bring up Settings.
- Tap Mail.
- Tap Sender Avatar.
- Choose Large, Normal size or have None by tapping it to place a check mark next to your selection.