Temporarily deleting app

Sean • Married to my best friend for 6 years, and after 4 years of tears and heartbreak are finally pregnant!
My wife was wondering if she deletes the <a href="https://play.google.com/store/apps/details?id=com.glow.android">Glow app</a> from her iPhone, will it remove all of her logs and data entered, or is that data stored on a server so that when she comes back to/reinstalls the app, it will re-populate?
Thank you in advance!