Would removing the READ PHONE STATE permission in my app make the app laggy and unstable? I removed both GPS and this premission because I thought that there was no need but now it is looking like most of the crashes are caused by this missing permission or is it because I have over 300 pdf in my app?

Adding content to your app (assuming it is a supported file type) shouldn't make it unstable. Any lag would depend on the size file being accessed by a particular screen as it loads. Also, this lag can increase if the file is being accessed from a remote URL - how strong is the end users internet connection? By remove do you mean you are going in to the source code and deleting sections of code?

@ koopakid08: I think you're asking about removing this permssion from the AndroidManifest.xml file. You didn't mention Android or iOS or what version you're running ;-) The phone state permission is only used a few times in the code, this means you can safely remove it from the manifest but will also need to adjust the places it's used. I think the only place it's used is in the Device.java class (going from memory here). Do this... a) remove the permission in the manifest. b) Comment out the code in the Device class where it's getting the devices screen size, and other details. Not sure if that's going to help or not but for sure a place to get started.