I've studied your Wireshark file. It's true in some reasons your iPhone sends the wrong value = -929993872. I've opened your project, for testing purpose change your server into Unified Automation demo server and change your tag Commando PV input source into ns=4;s=AllDataTypesStatic/StaticInt32 (one of static value of UA demo server). Import this project on one of my iOS device (iPhone 5s). Start and try to click buttons on Screen0. It works without problems and value of tag Commando changed as it should = 1,2,4. I've also tested on all simulators and all other my iOS devices and on all it works well. I don't understand why it has not worked on your device and I have only a few guesses:
1. Check version of TeslaSCADA2 Runtime installed on your iPhone and TeslaSCADA2 IDE on your PC (this last version 2.10).
2. What iPhone do you use? And what iOS version do you use? It seems to me that you use iPhone <4s. The minimum requirements for TeslaSCADA2 Runtime is iOS 8. Does your model supports this version of iOS. Do you have other model of iOS device? Can you check TeslaSCADA2 Runtime on it?
3. In your project you have button Invoer that let you change value of tag Commando through Dialog box. Do you have the same problem by entering value through this button?
4. Try to change Data type of Commando tag into other types (Byte, Short, Int, Long,Double, Float) without changing PV Input source.
5. Try to change change data type of Commando PV Input source in OPC UA server. Try to return to byte type, int16 type...