To install the ad blocker, simply go to your favorite search engine with your web browser from your Sony Xperia L1. Once there, you can type 'advertising blocker for smartphone', you will have access to a selection of applications and download links. You will then need to download an 'apk' file, corresponding to the desired application.
you must to read carefully the elements on each of the download pages. The previous step allows you to install the 'apk' files from your Sony Xperia L1. Just go to the folder where the file was downloaded and follow the instructions.
Once the steps have been validated, you will normally have blocked and removed advertisements on your Sony Xperia L1.