▁available ▁through ▁Google ▁Play ▁Store ▁due ▁to ▁ 4 . 5 ▁Non - comp ete ▁clause ▁of ▁Google ▁Play ▁Develop er ▁Distribution ▁Ag re ement . ▁This ▁is ▁the ▁same ▁clause ▁that ▁blocks ▁the ▁Amazon ▁App store ▁application ▁from ▁being ▁available ▁through ▁Google ▁Play . ▁Install ing ▁A pto ide ▁requires ▁users ▁to ▁allow ▁the ▁installation ▁from ▁" Unknown ▁sources " ▁in ▁Android ▁settings . ▁ ▁After ▁the ▁installation ▁of ▁A pto ide , ▁the ▁user ▁can ▁add ▁stores ▁( re pos itories ). ▁Besides ▁the ▁default ▁store ▁( App s ), ▁many ▁other ▁are ▁available ▁from ▁different ▁stores . ▁When ▁a ▁store ▁is ▁added ▁using ▁the ▁URL ▁of ▁the ▁store , ▁A pto ide ▁retr ieves ▁the ▁list ▁of ▁the ▁applications ▁and ▁stores ▁it ▁locally . ▁The ▁user ▁can ▁then ▁brow se ▁in ▁the ▁applications ▁or ▁search ▁in ▁the ▁Internet ▁for ▁other ▁stores . ▁ ▁In ▁June ▁ 2 0 1 1 , ▁A pto ide ▁Up loader ▁was ▁released ▁as ▁a ▁" s ister " ▁application ▁from ▁the ▁same ▁development ▁team . ▁A pto ide ▁Up loader ▁is ▁an ▁Android ▁app ▁that ▁allows ▁users ▁to ▁upload ▁to ▁an ▁exist ent ▁A pto ide ▁store . ▁ ▁A pto ide ▁Up loader ▁uses ▁the ▁available ▁A pto ide ▁Web services ▁to ▁upload ▁the ▁application . ▁The ▁submitted ▁AP K ▁file ▁is ▁kept ▁in ▁the ▁user ' s ▁store ▁where ▁they ▁can ▁manage . ▁ ▁For ▁the ▁user ▁that ▁wants ▁to ▁backup ▁their ▁apps ▁to ▁a ▁private ▁store , ▁it ▁is ▁advis able