试试这个网络画板：https://www.netpad.net.cn/

还有个叫mathtool的我觉得也还行：https://www.imathtool.com/

https://spk-resolv.spark-app.store/?spk=spk://store/tools/geogebra5
https://spk-resolv.spark-app.store/?spk=spk://store/office/geogebra-classic

https://spk-resolv.spark-app.store/?spk=spk://store/image_graphics/com.jihehuaban.cn

几何画板，desmos（函数画图，有网页版）