Correct short phrases

[Henox]

I have the following phrases in my CV. Are those sentences correct ?

1) Implementing new modules and improving code quality of existing ones in Web based
application for airlines.

2) It is a system based on deep neural networks whose purpose is to categorize text messages.

3) It is a Web application allowing users to create / join groups and lend / borrow paper books within these groups.

4) It is a Web application, the goal of which is to help manage educational sections at my university department.

 

[probus]

Just one tiny thing. Since you are using the plural in "Implementing new modules and improving code quality of existing ones", "applications". sounds better to me.

But it's pretty much perfect.