How to make photos taken by mobile phones larger than 30K?

If you use different zoom or digital zoom or different shooting methods, the camera will determine the accuracy of the picture according to these conditions, and the photos with low accuracy will naturally become smaller. In addition, if the color of the photo changes less (for example, taking a picture of a simple object), the size of the photo will be smaller, so if the photo is larger than 30k, the resolution can be improved, and don't zoom when shooting the object. If this still doesn't work, it can only be that your mobile phone screen is too small.