This is a frog shaped widget to show you the power left in your battery at a glance. if the frog is red you better plug in soon, if green you'll be okay and he turns purple while charging.
the percentage of charge is also shown clearly, on his flank.
if you click on the frog you'll see some options to see what's drinking all your juice and shortcuts to turn some battery drains off/on.
to install click menu>add>add widget>frog power
long click on the home page and add widget.
***this is a widget so you won't see it in your list of apps, just follow the instructions above***