Long Distance Games
One person texts the other the word 'Freeze!' and the recipient has to respond with a picture of exactly what they are doing in that moment. This leads to a compilation of a lot of silly photos over time.
Read My Lips
One of us mutes themselves and the other person has to read their lips to figure out what they're saying. It's really entertaining and you get to see your SO smile and laugh.
Bonus challenge: Play successive rounds of the game, like 'Telephone', and see how distorted the message can get.