Your comments

Textastic does have search and replace: tap on the loupe icon and then on "Find and Replace".

Edit: ah, you probably meant an iPhone text editor with search & replace, sorry.
Thanks a lot for your feedback.

There are existing discussions for all the points you mentioned. In the future, please search the forum before posting new entries. Each feedback item should cover only one topic.

Here are the relevant existing entries. You can add your vote to them:

2. Import Photos: http://feedback.textasticapp.com/topic/9278-import-pictures-from-the-photos-app/
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.

PHP code inside of <?  ?> or <?php  ?> is then highlighted correctly.
Thanks for the detailed description.

I tried to reproduce it but as you can see in the screenshot below it works for me as it should. Also, I could replace " dog" with " cat".

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.

Just to make sure there isn't another problem: are you using and iPad 1 or 2? Can you give me an estimate, how long it takes to launch the app?
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.

Das Einstellen der Sonderzeichen wird in einer der nächsten Versionen kommen.