One of my someday projects to create a generic self tracking app that presents a dashboard for quick entry tracking and visualization and syncs with a website. It will also export to a spreadsheet. It will also allow you to visualize data with graphs and so on. There will be a bunch of presets for various special types of graphs, like with blood pressure and so on. You could also specify zones for numbers so you can show 'red' for a danger zone glucose level for example.

Managing spreadsheets on a smartphone is very kludgey.