iOS: If you want to get any information about the Wi-Fi network you're connected to on your iPhone, you'd usually have to jump into the Settings. Wi-Fi Widget puts that info on the widgets screen.
With Wi-Fi Widget, you can easily see what network you're connected to and what the latency is. This is nice if you tend to bounce between a lot of different networks throughout the day. You can also optionally enter Wi-Fi passwords into the app, and get a share menu to quickly send a password to a friend. Wi-Fi Widget is a simple little app, but it does what it's supposed to do well, and it's pretty handy for anyone who moves between routers a lot.
Wi-Fi Widget ($1.49) [iTunes App Store]