I remember the times when developers were struggling to integrate with Yahoo!, Google, and other websites who have a lot of content. The web is a lot more open now. Websites are now opening up their content for 3rd party use. This is a good thing for developers.
Here are a few APIs that are worth looking at:
Google APIs
OpenSocial lets you integrate with data of websites like Facebook, Friendster, LinkedIn, Orkut, and other similar websites.
Google Data APIs lets you work with Google Base, Blogger, Google Calendar, Google Spreadsheets and Picasa Web Albums.
Google Maps API enables developers to build application on top of Google Maps.
Google Custom Search API makes users take advantage of the most powerful search engine in the web right now.
Google Calendar API helps you create and edit events, calendars, and gadgets for Google Calendar. This one's cool. I did a demo during the Globe event by enabling users update their Google calendars just by sending SMS.
Yahoo!
Fire Eagle give developers the ability to create location-aware applications.
Search BOSS lets application developers utilize content using the power of Yahoo! Search.
Pipes enables users to aggregate content from the web for personal or business use. There's a lot of tools here. Here's a sample pipe I created, an aggregation of all my blogs.
YUI is a Javascript framework which makes it easy to develop AJAX applications. I recently used this in one of my previous project.
Salesforce
Force.com API gives you the facility to embed into your application useful Salesforce.com features.
Ain't that sweet?! Now start building that killer app now!
Melvin Dave P. Vivas is Owner and Senior Consultant in Melvin Dave Consulting and Marketing specializing in IT consulting, business solutions, mobile services and technology products marketing. He is founder and Chairman of the Association of Filipino Java Developers(PinoyJUG), the largest community of Java Developers in the Philippines. He also invented the Lemongreen SMS appliance.