How do I combine up to 6 emails in a daily digest and return them to the group

Question

I work in a corporate PC environment using MS Office & outlook 2010 & 2013

We have recently used a free service called justinapp.io but have found it stopped working and would like to implement on our own

Essentially I have up to 6 users who send a plain text email each day That email is then combined in a digest and sent back to all users SO each afternoon we write our diary of what we did and next morning everyone gets that diary to read Pretty simple

Any ideas how I can implement an in-house system to achieve the same thing? Ideally we just do it via email - but could do with a text document and a batch Thanks for your help