Doing a reverse phone lookup is very easy these days. This is perfect for stalking unknown phone callers. Some of the lookups require a purchase to Intellius, which is worth the price for the amount of information you get for a person.
When writing eForms, it’s important to use the W3C validator to validate them. In addition, it may be beneficial to run any input received from an eForm through a purifier to eliminate any security risks.
PHP and do RESTful web services! I recently wrote a decent web service in PHP using the Slim Framework. One of the benefits of using PHP over Ruby on Rails, is that the time to configure and deploy a working PHP server is very “slim” and even free with Amazon’s AWS free usage tier.
If you are doing PhoneGap development, check some awesome tutorials on GitHub.