What Alternatives Are There to the Google Play Store?

Curious about alternatives to the Google Play Store (formerly the Android Market) for reading app reviews and downloading content? Read on as we explore some of the alternatives.
Today’s Question & Answer session comes to us courtesy of Android Enthusiasts—a subdivision of Stack Exchange, a community-driven grouping of Q&A web sites.

The Question

Android Enthusiasts reader Captain Toad is curious about alternatives to the Google Play Store (aka Android Market):

How many competing Android markets (other than Android Market itself) are there and are they any good?
I know that there are at least two others: SlideME and AppBrain which I have looked at and seem useful but which ones do you use and why?

So where else can shoppers go?

The Answers

Android Enthusiasts contributor Stefano offers not only a long list of alternative markets but what’s interesting about each of them:

There are actually several alternatives to the ‘official’ google android market. I personally like to search for new apps from my PC browser, and a bit less from my phone. Most (all?) of the markets nowadays offer both, via a dedicated phone-app that you’ll have to install… except from the official one which is already there.
Until, well, yesterday, the ‘official’ market would not have been available from your PC (meaning: on a PC web browser). Now it is, with a neat push-to-your-phone one click installation that is taking away one of the advantages of the competition (see appbrain). The alternative markets, though, have still their peculiarities… I’ll make a short summary but don’t expect it to highlight all of the differences. Some markets (eg. andspot) do not offer very specific features to users, but try to gather developers by offering advanced features such as easy stats.

• Amazon AppStore: latest big entry. countries limitations; catalog looking very promising with some (exclusive?) good pay-for apps; also features special offers and daily freebies. Def worth checking out if you’re in the US
• AppBrain: born to let you install android market application directly from your PC web browser, also allows you to discover new apps based on the ones you have. It’s a meta-store (my favourite before the official market update)
• SlideME: they provide applications to niche markets, based on geographic location, payment method or even types of applications that users can’t find in traditional channels
• Samsung Apps: samsung app store, which of course requires you to own a samsung droid phone
• AndSpot: focused around an app for sharing and discovering apps
• appsfire: yet another app for discovering official market applications (iOS/Android)
• PocketGear by appia.com: a huge, cross-platform (symbian/android/java/winmobile…) market
• aproov: a quite different web look. register to download via a specific phone app.
• MobiHand OnlyAndroid: more focused on (expensive) pay apps, but offers discounts and free deals
• GetJar: my latest discovery. Quite a lot of apps, and they have specials (“GOLD”) commercial apps for free. Extremely interesting platform for developers, since they seem to offer above-the-average marketing and PS activities!

[Also] a lot of review/forum sites will link to one or more of these markets, eg androidtapp or androidpit androlib.
I suggest you click on some of these links and see for yourself if the look/applications suit your style!
Various sources and in particular this thenextweb.com article.

Source: http://www.howtogeek.com/169538/what-alternatives-are-there-to-the-google-play-store/