I live with a 16 GB phone in 2021
My old 128 GB phone broke 2 months ago, and after realize that nobody could bring it to life again (I live in Cuba, there are no specialized tools, technicians, etc… to fix a SAMSUNG smartphone), I needed to buy a new phone. But wait, I live in Cuba, and due to coronavirus pandemic, everything is more expensive than ever; I am a student, I cannot afford everything, so I finally bought an used gold iPhone 6s… 16 GB version.

In the first two weeks I restored it 2 times because the storage was filled very quickly. Almost 5GB of memory is used for iOS 14.7 operating system, and I think that number will increase with iOS 15. It’s impossible to have installed all the apps I previously had in my Samsung Galaxy. I needed to find a plan for having only the most important things saved in it.
I have some advices I want to share with you:
1 — Keep the gallery empty and use the web version of Google Photos. I upload every two or three days every picture in iOS gallery to the cloud, and when I need one, I access it via Safari and download once.
2 — Only download the apps you use everyday. If there is a web version of the app, pin it as a bookmark to the Home Screen. Personally, I only have Twitter, WhatsApp and Telegram downloaded, and 15 web versions of app pinned.
3 — Delete WhatsApp chats regularly. I use to generate almost 200 mb of chats every week in this app.
That is all the tricks I use. Let me know if they were useful to you.