Galaxy A7 unresponsive Multi-touch

[Vennece]

Hi, I'm new here, this is my first post to be created, I had posted the same issue in previous post then redirecting me here as the local community

[EllisKai · Accepted solution]

Boot to safe mode and observe for a while or try to replicate the problem.
You won't be able to use third party apps (and I think developer options will be disabled).
If you don't have the same problem while on safe mode, it could be caused by a third party app - you'll need to figure out what is it and uninstall it or change some of its settings and/or permissions.
If you still have the same problem while on safe mode, it could be caused by the UI, native apps, or (more probably) the hardware itself being faulty/damaged - you might need to have it repaired.

Are you not using a tempered glass or screen protector?
You might need to check if it was installed properly or if it's not preventing the screen to work well.
Have you ever dropped or pressed the screen too hard - lied down or sat or stepped on it; or dropped it in water?
Did you modify/increase touch sensitivity?
Try turning touch sensitivity off and compare the touchscreen performance vs when it's on.

You said you've done factory reset? You can try to remember the changes you've made in the settings and try to revert them back to default one by one to figure out (isolate) the cause of the problem.

[Vennece]

Thank you for your reply.

It was the hardware problem as I tested booting into safe mode and test its multi-touch on the same website, before that, tested the touch sensitivity, it did improve sensitivity (even not touching the sceeen at the very small gap), but unfortunately the multi touch is a separate issue, as the touch sensitivity is enabled and placing multiple fingers then swiping all at same time or wiggling, the touch becoming unresponsive 

I've done another two factory resets yesterday, one for default apps and settings, and one also without doing a software update, at the end it still occurs, at least doing that to know the issue came.

Marked your reply as solution cause it helped me to detect the issue causing from.

For now and at least the bit of solution I found is currently I do to fix, sometimes, still tedious to do, until I get a new phone, I'll post an update someday if I found an absolute solution, if i haven't since then, I already moved on to another new device.

Also i'm not a hard toucher to press a screen even pressing an actual keyboard or mouse, I never hard and harshly press any of a button, but this phone is second-hand, so i have no known history of damaging. I discovered the issue when I was using a drawing app, I use left hand for pinching to zoom in and out while simultaneously at right hand draws the brush, I've done it many times on different devices that supports multi-touch back then.

[EllisKai]

I tested my device in the same website using 10 fingers and sometimes the touch won't register if the fingers really quickly get too close together. I think the website or the screen itself is assuming that the touch points merged so it would only register one instead of two fingers.

There was also an instance when the website didn't quite capture the touch point but the screen did (the white dot in the photo).

If other than this website, you only experience this problem in one app (or drawing apps), it is possible that the app wasn't optimized for your current device, or the device wasn't really made for such applications - I mean it could just be one of the device's limitations so that won't prove that there's something wrong with the touchscreen itself - you would then just need to upgrade.

Back in my older phone, I could trick the touch screen to interpret a swipe gesture by just touching it with one finger then quickly altering it with another.
I can't do that on my newer device yet.

[TeamGalaxyBianx]

Hey there, Vennece! First off - welcome to the Community! 🥳 

Now you've mentioned that the problem still persists even in Safe Mode. At this point, your best bet would be to take your Galaxy A7 to a nearby service center to have it diagnosed and repaired. You can go ahead and book an appoint directly from your Samsung Members app, right under the Support tab, or you may dial #GALAXY 😊