I think there is still hope for improved accuracy from our cell phones with the dual frequency chips. I found an article where they tested the Xiaomi Mi8. They were able to achieve decimeter accuracy through post processing and sub-meter real time. Looks like the software is behind the curve, hopefully that will change. Here is a link to the article, it is a pdf. https://www.mdpi.com/1424-8220/19/11/2593/pdf
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