Backstory: A lot of my friends are having kids and there are 100s of apps out there that post the 1-12 month pictures that are all cute and fancy. I've also seen parents post pictures of their kids holding chalk boards with the "first day of school" stats. I got to thinking, once kids reach 1, there are no apps to save and show progress/growth.
The Idea: An app to record a child's progress through pictures.
Deep Dive: You would create an open platform where parents can take progress pictures of children. Parents can record pictures and tag them with memorable dates or experiences.
You would also create a portal for photographers to join. Allowing photographers to join in the mix gives parents the ability to connect to local photographers for professional photos. Different photographers could take pictures at different stages of the child's life as long as both the parent and photographer are connected to the app.
Another great feature is making each child's album a progress web app. This is where users can make the specific album page a link on their smart phone home screen. Family members would love this, they would essential save the album to their phone with similar functionality to a native app.
Validation: There are tons of baby picture apps and https://www.stickyalbums.com/ has inspired the "download" this album feature explained above.
Monetization: You could charge a small monthly hosting fee for the photos. You may also be able to charge photographers a fee to upload professional photos rather than have a joining fee. This would encourage photographers to join and only pay when they get bookings.