Here is my product: https://matchkraft.com/. It is a marketing toolkit. I think you need to ask for feedback, asking why users don't want to pay for a premium subscription. So far, you are getting new users that is a good sign you are going to the right direction. Maybe, who is your ideal customer or maybe your product is ok but need more visibility (maybe paying ads). Try to get active users. I really want to... Source: 12 months ago

Calling a 3rd party API: There is a complete ecosystem providing "google-sheets-as-DB". I personally tested and recommend https://sheetson.com/ but there are a lot more with free tiers https://sheetsu.com/ https://sheety.co/. Source: about 2 years ago

a preview of the image improved thanks to "letsenhance.io". Source: 6 months ago

Enhance. io- the AI-powered image enhancer that increases resolution without losing quality. Customize dimensions, improve texture, tone, color, and clarity effortlessly. Ideal for WordPress eCommerce sites, real estate, and websites with multiple similar images. Save time with automated presets and clean up images using Smart Enhance for crystal-clear visuals. - Source: dev.to / 10 months ago

Https://letsenhance.io (For $9 you can get 100 credits to make 100 thumbnails enhanced to HD Quality and you can use the image generators). Source: 12 months ago

Https://letsenhance.io isn’t free but for $9 you can get 100 credits to make 100 thumbnails HD. Source: 12 months ago

Then upscale the image - https://letsenhance.io/. Source: 12 months ago