Just in your history, e.g. as such:

  Company 1, Location           StartDate - EndDate
  Role
  I was responsible for implementing an iOS tablet app and 
  provided guidance to junior team members. In the end I did 
  have to leave the company after x months due to the start-up
  failing.

  Company 2, Location           StartDate - EndDate
  Role
  ... 

You might have to change the layout of your CV a bit. Personally I have the following sections on my CV:

- Contact Info

- Professional Experience

- Education

- Programming (I should rename it to 'Skills' or something)

- Certifications

- Languages