Currently, files are closed when you switch to another file and the undo history is lost. I'll consider saving the undo history when switching files.

Thanks for letting me know! I'll try to fix it.

You need to select "HTML" as the syntax definition. This is the default for php files.

Thanks for the detailed description.

I spent the evening optimizing the start-up time of Textastic. For me it is now about twice as fast. On my iPad 2 the app launches in about 4 seconds now. This optimization will be available in the next update.

I hope I can improve performance by loading the syntax definitions when they are needed instead of at application startup.

Um PHP-Fehler anzuzeigen, müsste Textastic einen PHP-Interpreter mitliefern oder die Daten an einen Online-Dienst schicken. Ich werde mir überlegen, ob das vielleicht in einer zukünftigen Version umzusetzen ist.

Textastic loads all syntax definitions on startup. I have already optimized the startup speed but I hope to further improve this in the future. I don't think there's anything you can do about it.

Maybe it's a tab character instead of space? You can search for tabs with "\t" and for newlines with "\n".

You can also change the tab width in settings.