The best free App for android mobile for hiding photos and text with password is private diary App. This App functions like a basic diary. You can work in it offline also. All the data in this diary is only visible after filling correct password.
In this diary you not only write with password protection security but you can also keep photos from storage or directly by clicking from your mobile camera.
Any data in private diary app is stored in SD card in encrypted form.
You can open it with password only (if diary option is locked with password). No one can see the photo or text you written in private diary unless he know the password.
This app is totally free. You can also create backup file online with username and password. Even if your mobile will lost, you can get back data from online account. you can synchronize mobile data with online data anytime.
You can also send email all your text and photo of this App. There is option of writing in it by speaking (through Speech to Text software), but you will find lot of error in conversion the speech into Text.
Its very useful app available on Google play store at This Link