Okay, I have an Xperia E android 4.1.1. It has 2 GB internal space and so I got an 8 GB SD card. I noticed that any app I download occupies space in my internal memory. I tried moving them to SD card but I can't do it in the way given on Google - Settings>apps>manage>move to SD card. When I go to my settings I don't get any Manage Applications. I just get my apps and there are options like Move to phone or Move to Internal Storage. I also tried App2SD. But it didn't work. Isn't there any other alternative than rooting my mobile? Please help
Android no longer natively supports moving apps to SD Card. Some manufacturers that ship phones with SD Card slot (like Samsung, for example) often do include this functionality. Apparently Sony is not one of these manufacturers, so you will not be able to use your SD Card for app storage with their stock firmware.
If you decide to root your device, you will be able to use apps such as Link2SD to move apps to your SD Card. Note that you will need to re-partition your SD Card (and re-format it) in a special way to be able to take advantage of this feature. You will also not be able to easily swap the SD Cards in and out, as it will become an "extension" of your phone's internal memory.