Thank u for this interesting input! But then again that's not real measurement of widespread usage.
I can run script that sends transactions from one account to the other and appear like the network is widely used. But in reality it's just me.
~CfA~
Wouldn't that cost you?
If answer is Yes i am sure no one does it.
so answer on your question is only one Ethereum.
Before i checked bitinfocharts.com i would expect it is Litcoin. Sadly bitinfocharts.com dont offer transaction infos of all big cap coins.