There are many measures to free up space in Android phone. However, I'm afraid that they won't make too many differences since nowadays apps are of fat size and HTC One SV has limited memory. Nevertheless, you can try what you can do.
Firstly, back up your phone data in case they are lost during this process. Do it with HTC Sync Manager or other tools.
Second, analyze your phone storage and know what kinds of files are filling your phone besides the four apps. It seems that HTC One S doesn't provide detailed analysis, so you may have to install an app, Storage Analyzer & Disk Usage is good and of small size. If you cannot install any app now, do it after the method below. After the analysis, delete useless files or move files to SD card in File Manager.
Third, try moving apps to SD card. Go to Settings> Application manager, find one of the four apps, tap it, choose Move to SD card if there is an option like this. Only some apps can be moved to SD card.
Note: In case you delete any important data by mistake, recover those phone data with iReparo for Android as soon as possible.
Edit by Admin: Links to external site removed.
— modified on May 10, 2017 12:57:51 AM