Android: Adding a PIN, password or pattern to your phone's lock screen can be great for security, but really annoying if you unlock your phone frequently. Delayed Lock turns off your pattern for a few minutes, so you don't have to swipe it every time you check your phone.
If your phone's sitting in your pocket, it's a good idea to keep it locked. However, if you're sitting there playing with it—having a real-time text message conversation, compulsively checking Twitter, or otherwise turning your phone on and off repeatedly—swiping that lock pattern can get really annoying. Delayed Lock customises when that lock screen shows up. So, you can tell it to wait five minutes after you lock your screen to turn it on, so your phone stays safe but gives you frequent access when needed. The time period and other options are super-customisable, and you can also install plugins that disable the lock screen when you're connected to a specific Wi-Fi network, Bluetooth device or GPS location.
HTC phones already have this built-in, but don't give you nearly as many options. If you're using an HTC phone, however, you can combine Delayed Lock's customisability with HTC's feature set by checking the "Use HTC Sense Delay" box. Similarly, if you use previously mentioned WidgetLocker, Delayed Lock has some options for playing nicely with that app as well.