Android Slowness/Hanging Problem Due to Big file in DCIM/.tumbnails folder
If you are using an android smart phone and it is getting slow or hang then look in DCIM/.thumbnails folder there will be a .thumbdata* file will be there with big size Delete this file... and create a folder with same name in place of that file. This will resolve your issue. I solved mine this way. Please write in comments if this helps.