The best replacement for app store is google play.

The best alternatives to app store are rated as following:
★★★★★  google play
★★★★★  itunes
★★★★  android market
★★★★  itunes gift card
★★  windows store
★  google play revenue
★  marketplace
★  mac app store
★  cydia
★  market
★  apple app store
  android market sales
  itunes store
  google play free apps
  android store
  app world
  play store
  google store
  itunes card

Your alternative for app store is not listed? Suggest!
Speaking about app store, one probably shouldn't forget about free apps.

Other search terms related to app store and their ratings are:

★★★★★ free apps
★★★★★ jailbroken iphone
★★★★ snow leopard
★★★★ itunes gift card
★★ flappy bird
★★ touch id
temple run
You have in mind a companion for app store and it is not yet here? Propose!

Google Trends

Scale is based on the average worldwide traffic of app store in all years. Click on graph for more.
app store
google play