Sometimes Tapatalk will ask "do you want to retrieve the post you were writing?"
Otherwise no.
Using a web-based editor is always fraught with risk, too many moving parts, any one goes bad your work gets dumped into that great big bitbucket in the sky.
Better to compose long screeds in a trusted locally-saved plaintext editor app, ideally an auto-saving one,
then copy and paste into the forum UI only when you're all done.
I like Simplenote, free & FOSS, cross-platform and automatically sync's across all your devices, great fulltext search
Also tagging support so can function as a minimalist note-taking templating knowledge base if you don't require more structure, no hierarchical outlining support for example.
If you want that latter, Workflowy is a great tool, also cross-platform, automatically sync's across all your devices, great fulltext search and tagging support. But not FOSS, and if you use it a lot no longer free.