No credentials needed for Sqlite database?

I am not quite getting the idea of sqlite database. I am developing a hybrid mobile app using Ionic Framework and backend with PHP.

I referrred to this article for using the sqlite http://ift.tt/1zsfJve

I have a few questions now,

1) So, anybody can create a table,insert and do any kind of operations? Is'nt there any need of a security method to access the DB like mysql?

2) Is a separate instance of Sqlite created for each application? Coz if not,I can make a guess for a tablename created by any other application and delete it all together,isn't it? I just dont get it?