Android bootup crash

After a couple days of playing Minecraft after I purchased it from the Google Play store, it worked fine...until yesterday(Sunday). When I went to play Minecraft Pocket Edition, it went to the bootup screen(the Minecraft logo with the white background) then exited out of Minecraft. Ever since it's done the same thing over and over and over and over again. It won't let me play Minecraft. PLEASE HELP ME!!!