I've heard that if a website or an app appears in a weird way, it means that your device might have been hacked. I have Android 8.1 Oreo, and below is the Amazon Shopping app showing 'null' after the product price.
What is the cause? Is my device hacked or infected with malware?
Seems like an issue on Amazon's side, I would guess that the app was coded to add a currency symbol like $ or € to the end of the price tag. Since the currency currently used is on the beginning not the end, seems like the app is also searching for something to add to the end, but adds an unset variable instead causing it to display "null". That is my theory tho. On the other side if you are worried about getting malware, use a scanner to scan for malicious apps. But it is unlikely that you got Malware if you haven't downloaded any shady apps from outside sources or sometimes Play Store. There is no known way of bad people simply getting into your phone without running malicious code first, either packed in a "shady" app or using an exploit of another app...
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