Check-in

1. Consider the following sentence:

"I received regular check-ins and encouragement from many of my clients and friends who were aware during the process."

Does 'check-in' mean 'visit'?

2. And would BOTH the word 'check-in' be appropriate to use:

a) to express that someone came to see you at the hospital?

b) to express that someone came to see you at home?

3. (Assuming that both mean the same), which is MORE FORMAL: 'check-in' or 'visit'?