This is app that allows you to read around 100 free “web comics” These are comics that are released online as opposed to printed. This is my most popular app.
This is a Bitcoin related app that allows you to explore the blockchain. See how coins are sent from one address to another and find out what makes up a transaction. You start by entering the id of the address, block or transaction you are interested in. you an eityher enter this as text or by scanning a QR code.