You can add me on WhatsApp

[Cunning Fox]

When I'm giving someone my number and telling them to text me on WhatsApp what preposition should I use to sound natural:
1. Here's my number. You can add me on WhatsApp. (I've always used this wording).
2. Heres' my number. You can add me in WhatsApp. (I'm not entirely sure whether it's outright wrong).
3. Here's my number. You can add me to WhatsApp. (I think this one is OK but less idiomatic than the first suggestion).

 

[emsr2d2]

When I'm giving someone my number and telling them to text me on WhatsApp, what which preposition should I use to sound natural:

1. Here's my number. You can add me on WhatsApp. (I've always used this wording.)
2. Heres' my number. You can add me in WhatsApp. (I'm not entirely sure whether it's outright wrong.)
3. Here's my number. You can add me to WhatsApp. (I think this one is OK but less idiomatic than the first suggestion.)

I wouldn't use any of them. I'd say "Here's my number so you can WhatsApp me" or "... add me to your WhatsApp contacts". However, of your three, I'd use "on". For me, "in" doesn't work with apps generally, and "You can add me to WhatsApp" doesn't make sense. You can't add other people to WhatsApp. Only you can choose to download WhatsApp and share your contact details.

 

[teechar]

text me on WhatsApp

That's what people say. You can also use "call", "contact" or "message" instead of "text".

 

[emsr2d2]

That's what people say. You can also use "call", "contact" or "message" instead of "text".

And "WhatsApp" is used as a verb these days. I'd just use "WhatsApp me".