The Share Sheet
Once you've dowloaded the app, you may have to go through 3 simple steps to have the share sheet show up for you. Open the share sheet and then:
1. Scroll all the way to the right and tap the More button
2. Tap Edit in the top right
3. Find the Aboard logo and tap the + button on the left of it
Optional step:
Drag Aboard to the top of your Favorites Apps list, this way you will find Aboard without having to scroll through the list of favorite apps once you open the share sheet.
