Actually, I believe that each use of the is grammatically correct.
In order to determine which one is "correct", we need more context. In other words, you have to choose the one that is most appropriate for your work.
I will help you understand what each one implies.
Including the in the development can imply that there is one kind of development, or that you had a particular development in mind (and you introduced it earlier). Omitting the from the web applications implies that you are speaking broadly about web applications in general.
Omitting the from the development can imply that you are talking about unspecified/unnamed developments of the web applications. Including the in the web applications suggests that you have certain web applications in mind, and it also suggests that you introduced it earlier in the work/paragraph.
- Including the in the development can imply that there is one kind of development, or that you had a particular development in mind (and you introduced it earlier). Including the in the web applications implies that you are talking about certain applications which you introduced earlier.
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