I’ve actually used one of the blocks, sir
Dear @Salman,
I made a simple project to show the difference between the two events.
https://x.thunkable.com/projects/5f560414af6aa42e17ec1245/3907f726-4eb2-438f-ba3a-e18ee3c88504/designer
The project has two screens (home and test) if you start the project and move between the two screens using the buttons provided, you will notice both counters are equal every time and you will notice no difference apart from [Starts] event is fired before [Opens] event.
After moving between the screens 3 or 4 times using the buttons provided, now start going back using the [Back Key] of the phone or using the [Swipe Gesture] and now notice that the [Opens] event is fired but not the [Starts] event.
Hope this makes it a bit clearer. 
2 Likes
I’m Still Confused Sir, So what is the conclusion of the project
I was thinking the sample project will make it clearer but it seems I was not able to pass on my thoughts to you. Let’s see if any of Thunkable staff / experts to put it in a clearer way 
hmm, I’ve tested your project and it doesn’t make any difference
You meant to say you could not see that when you were going back and forth between the screens using the buttons and when you use the swipe gesture you got different results!!!
We’re you noticing the difference between the two counters when you were using the swipe gesture???
I tested your project using an emulator from Thunkable, I am not on a mobile and indeed I did not see any changes in the emulator
1 Like
You need to use Thunkable Live App on the mobile. The web test emulator however even the web emulator should give the similar results. I watched the video clip you posted and could see why you can’t see any difference.
First phase use the buttons to go back and forth between the screens and let both counters reach 4 or higher.
Second phase use ONLY the back arrow number of times. You will see the screen alternates between home screen and test screen and when test screen appears you will notice only one counter is incremented. At this phase DO NOT use the buttons on the screen but ONLY the back arrow.
Have fun with it 
How to use it
1 Like
Download it from Play Store
Okay Thanks.
I’ve tested your project on my phone and the results are same, Please watch the problem here :
1 Like
Dear @Salman
As I explained earlier, first use the buttons few times then use the arrow few times but DO NOT mix them.
When you use the back arrow. Just use the arrow few times and do not use the buttons on the screen. ONLY USE THE ARROW.
When you click on the arrow few times you will notice the difference.
DO NOT mix the arrow with the buttons. USE ONLY THE ARROW.
I have tested it without mix, but it doesn’t work, the only difference is the “open screen” requires a slightly slow response.
Please Watch The Problem :
I see the 5th time looks strange, sorry sir, I am still confused by such a difference and what is the use of that difference, even though we need a difference not at the 5th time and “Back Pressed” to see different results. 
Okay, here’s the simplest example. Open the app and first click on the Go Screen2 button, and then on the Go Screen3 button. These screens have a Label with the names of the screens. How are these labels displayed when you go to Screen2 and Screen3?
https://x.thunkable.com/projects/5f5f486743fb5af0585187f1/project/properties/designer/
still can’t work,
See the problem here :
What’s the only difference is, “Open Screen” gets rid of the label but it’s a little slower
No, you’re wrong. Your video clearly shows the difference between Start and Open. On Screen 2, you don’t see the Label because it is hidden in the Start block, and on Screen 3, you see how the label is made invisible because it is hidden in the Open block. Now do you understand the difference between Start and Open?
A strange difference, but it’s still bugs right
Why do you think these are errors? There is no mistake.
The [Start] block is executed when the screen is already created but not yet displayed, and the [Open] block is executed when the screen is created and displayed.
Now show me a video of this project that shows a different difference between Start and Open (go between Screen1 severel times)
https://x.thunkable.com/projects/5b1fa047c1b0c8cb896dfa10/project/properties/designer/