I take care of textfields this way; hide them on a bottom layer and drag outside of layout. Then I use a sprite with number graphics from 0 - 9 ( 10 frames ) to display whatever is in Text1,2,3,4, whatever ( usually timer, score, health pct. ).
You could do the same with letters, but I find that most text that needs updating uses numbers anyway. I started doing it this way because it looked better, I could use any font and effects I wanted to without making each number anything more than a frame in a simple sprite.
Seems that also works better as far as optimization goes too.
The only game I have on the arcade here has a timer done like that: https://www.scirra.com/arcade/sports-ga ... 18939?cp=2
Not sure about iPhone, but on a 5 year old laptop CPU usage is around 2-3% when playing that game
But why use a text object at all? You could use a variable or arrays to store the text that should be displayed. Your way seems like a very unlogical way of doing it. Sounds like you should just use spritefonts instead which is exactly what you need without the unnecessary events. It works just like the text object but a lot more optimized. Just set the text with one event and you're good to go.
The regular text object is mostly used for debugging and should never be used in any form in final builds.