Hi just through trial and error, if you want to delete emails but not all at once, to speed up selection
1. Sort in the order you want it by name or date etc.
2. Highlight the bottom one to start from.
3. Then keeping finger on the screen, start to slide up and the screen will start rolling up selecting the emails above it and highlighting them
4. Select delete
Great little feature saves loads of time if wanting only groups of email deleting them all .....well done samsung