KOReader is the best eReader software I've found. It works beautifully on eInk screens, Android, and Linux. Just a gorgeous - and infinitely customisable - experience.

There's one thing I don't like - to move forward a page, you have to click the right of the screen and, to move back, the left. That's fine if you're holding the book in your right hand. But sometimes I behave in a sinister fashion and hold it in my left. I want to tap the bottom of the screen to move forward, and the top to move back a page.

My previous eReader had an easy-settings menu like this:

KOReader doesn't have anything like that - yet - so here's how to set it up manually.

1. In the book selection screen (not when reading a book) tap the top of the screen to bring up the menu bar, then press 🛠️ for Tools
   
2. At the bottom of the menu, scroll across to page 2
   
3. Select "More Tools"
   
4. Select "Advanced Settings"
   
5. Read the big scary warning message and press "OK"
   
6. Scroll along until you find "DTAP_ZONE_BACKWARD". Tap on it, and edit the values to read h=0.5 w=1 x=0 y=0
   
7. For "DTAP_ZONE_FORWARD", set the values to h=0.5 w=1 x=0 y=0.5"
   
8. Press the "X" in the top right corner, and restart KOReader.

Done!

Adapted from this GitHub issue. I've also added these instructions to the KOReader Wiki