This cookie's perspective, perhaps influenced by tones
Bottom's after Siwa, the Nome(sp?) of round stones
If money's a coin, the cream's the flip side
Top's where you look when you know you've replied
Hint 1:
The suffix is easier if you know Assassin's Creed: Origins. The infix is a common idiom. The prefix is a staple feature of any messaging service.
Hint 2:
The full word is closely related to greeting cards and also related to certain cookie jars (hence the cookie theme)