AndroSS

AndroSS is an app that lets you configure the way you take screenshots on your Android device. To use the app, however, your device must be rooted or have Tegra hardware. Please note: if you do not have a rooted device or Tegra hardware, the app will not work properly.

In the settings, you can determine whether you want to take screenshots in JPG or keep the default PNG format. You can even decide to use a version of JPG with higher compression (much smaller size, but lower quality).

Other options let you keep the screenshot open (by default, it closes after you take it). You can also change the folder where all your images are saved.

AndroSS is an excellent app for anyone who takes screenshots often. This way, you can take them as JPGs and save tons of space on your device's memory.