Installing and uninstalling apps from your Android Jelly Bean phone, such as a Samsung Galaxy S3 or Galaxy Nexus, couldn't be much easier, but there are one or two tricks you can try to fix problems and keep your phone running smoothly.
For example, if there are apps you're not using on a regular basis, clearing them out will free up memory and ease the pressure on the internal storage.
The following examples were carried out on a Galaxy Nexus, which runs a pure version of Jelly Bean, as Google intended it. While the Galaxy S3 features Samsung's own interface tweaks, you'll find it's almost identical for the purposes of this tutorial. And if your phone is running the earlier Ice Cream Sandwich flavour of Android, you'll find the same is true.
Installing new apps
Visit the Google Play store, sign in with your account details, and you can ping apps straight to your device from the web. The 'Recommended for you' section showcases apps you might like, based on what you've already installed and even where in the world you are (you know Google knows everything about you, right?).
Click the Install button on an app and if you have several Android devices you can choose which one receives the app, over the air, within seconds. Fire up the Play store app on your phone and you can find the same screens and categories.
If you want to be able to install apps from sources other than the Google Play store (alpha and beta releases, for example), the relevant option is on the Settings > Security page. Do not activate this unless you're happy the app in question is from a trusted, known source.
Apps can be updated by visiting the My Apps section of either the Google Play website or the Play store app on your phone. Delve into the Play store app settings and you can configure whether updates are downloaded and installed automatically, and whether this only happens via Wi-Fi (to save on those data limits).
There's also the option to automatically add any associated home screen widgets for each of the apps that you install. If an app update modifies its permissions, you will always be prompted to confirm the installation manually.
Head into the main settings screen, open the Apps page, and you might be surprised at just how many applications are operating in the background (under the Running column). Tap the top right-hand corner to switch between running services (apps that are actually running), and cached processes (temporary files stored in memory to improve loading times). The available RAM is shown along the bottom.
Any of these apps can be stopped temporarily, though in most cases you'll need to use a third-party app manager to prevent them from relaunching next time you reboot the phone. If a particular app is misbehaving, stopping its associated processes and relaunching it may resolve the issue.
App settings and removal
Switch to the All column, tap on an app, and you can find options for clearing its associated data (your username and password, for example), and its stored cache (temporary files held for quick access). You shouldn't need to use these two options, but they can help when trying to troubleshoot problems or reset an app.
Unless the tool is a built-in Android app, you'll be able to uninstall it from the same screen. There's also a list of the app's permissions, and the option to clear any default associations you've set (if you want to change the browser used to open web links, perhaps).