Keep the app free, and if ad-free, keep it like that. Try to make it bigger. This is your investment in the future. If you have an app with +1 or +10 million installs, that's a beautiful item on your resumé. If you really want to use that app for money, create new functionality via in-app payments, or give all old users a life-time free version that can be transferred to other devices. Better use it to attract attention from investors and let them give money to you for a second app.
it is but a bird int he hand is worth 2 in the bush. Got to wonder how many people saying use it for resume have had a similar experience, used it for resume and then gone on to their dream life vs people who tried to monatise, maybe failed but learnt something along the way. Personally no experience of either but when you have soemthing its always worth attempting to leverage it, you still have the figures later even if you fubar
