Mochi's API is actionscript/Flash-only, just like their ad and micropayment systems :( . Are there any other solutions for plug-n-play APIs like this?
I believe SmartFoxServer and Neutron include support for high score servers and are Unity-compatible. But they might be overkill if you only want to track high scores - a tutorial for setting up a simple high score server is on on the Unify wiki.
There are some Unity forum threads on using the iPhone "social gaming networks" OpenFeint, Scoreloop and Agon Online, all of which provide leaderboards, and at least Agon and Scoreloop have Unity scripting interfaces (not sure about OpenFeint)
Looking For LeaderBoard API’s ?
My problem was also consolidated as two months ago, then someone told me about
Shephertz cloud API’s, I am using these API’s from last two months.
This works totally fine for my game. I am really very impressed from shephertz’s API’s.
They have Bunch of API’s Which Suits our requirement.
Explore this LeaderBoard Service and you’ll surely get the solution for what you are looking for.
CheckOut this Unity3D Sample, I think It Helps You a lot.
https://www.leaderboards.io - is a great leaderboards service. you can create as many boards as you want and you get top 100 scores for several timeframes (today, yesterday, this week, etc) and social leaderboards. Its easy to integrate with; uses a cross platform JSON REST api.