help needed with diary type app

[nelle]

hi,
i am in the process of designing a diary type at for university students

it will have all the usual diary functions which i am fairly alright with making in this point in time. e.g calendar, to do lists etc

but to make it more interesting i want to add a social element to it, i have been thinking about adding a function where students can

• log into the diary/app
• add comments about lectures under lecture headings

so for example:

student-a would start up the app, login, go to the lectures option, click a lecture heading and be able to add a comment, saying "i dont understand ......"

student-b already logged in could view the lecture comments and post a comment suggesting a link where student-a could get more help.

has anyone got any idea where i could start with finding out information on how to create this type of function in my app.

any information with regards to what i explained above would be greatly appreciated

also feel free to give me any other ideas on how i could make my existing diary app idea more sociable, maybe a sharing function.

thanks