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If you have arrived at this page via a link from a related Help site then just enter a word or phrase that identifies the topic into the search box [next to magnifying glass icon] to retrieve any matching results. 

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If you would just prefer to browse the site then access the other pages using the menu options to direct you to the relevant information. 

Play Store:

The most trusted home for Android Apps for most people is probably the Google Play Store. There are other locations to download applications from [some trusted and some less so] either way always be careful, and be aware of potential security issues. If you are not sure of a location try Googling it first to see what others have to say about it.

Click here to read an article by AndroidPit that explains a few things that the Play Store can do for you that you might not already know about.

Click here to read another article, this time from NextPit, that can also help you sort out issues with Google Play Store which should be your primary option for downloading and installing Android Apps. 

It also mentions alternative ways of installing applications from other sources but remember these may not always be as secure. It is advisable to research Apps / locations before going ahead and installing them yourself.