How much information do you have stored on the Internet? I use Gmail, Facebook, Twitter, Dropbox, and LinkedIn just to name a few Internet services where I store personal information, all of which amounts to my personal cloud. In order to find something I have to access each of the services individually, which can be very time consuming. Greplin is a search engine that indexes the information you store in these services allowing you to search for information across all of them from one web site, and they have released an iPhone app.

Greplin was first released August 2010 in private beta, and is now publicly available. The service utilizes the freemium model, and you can index Gmail, Facebook, Twitter, LinkedIn, Dropbox, and Google Docs for free. If you use services like Evernote, Yammer, or Basecamp, you can pay $49.99 per year or $4.99 per month to index those services. You also can earn the ability to add Google Reader, Del.icio.us, Tumblr, and Reddit for free by inviting others to use the service, although those services are also included in your subscription.

The first thing you will want to do after signing up for Greplin is to add your accounts to the service so that it can build an index. Greplin uses OAuth to login to the services, which means that it doesn’t store your credentials. You should be aware, however, that the service does create and store indexes using the information it finds in these services, so if you have a problem with that you might not want to sign up to the service.

After installing the iPhone app you need to provide your Greplin login credentials, after which you have the ability to search for information. The Greplin app accesses appointments on your iPhone calendar and uses those for suggested searches, and it stores your most recent searches. I did a test search using a personal name, and Greplin returned items from LinkedIn and Twitter. Greplin searches Twitter for items in your Timeline as well as your Favorites. (In my testing I only connected Greplin to LinkedIn and Twitter.)

While there isn’t a Greplin app for Android, the mobile version of the Greplin web site, which is what you use to run searches from desktop computers, works very well. My one complaint with the mobile web version of Greplin is that it doesn’t have a simple way to clear the search box, you have backspace to delete previous searches.

After my brief testing I find Greplin to be an incredibly useful service because it quickly and easily retrieves your information spread through multiple web apps. The iPhone app is free and available now in the App Store.