Is it necessary to update android apps Recently i got a new android smartphone and i want know if its necessary to update android apps frequently.The reason for asking this is

1)does updates for android apps reduce the battery usage?

2)should i update my apps if i don't have much internal memory (i mean will it slow down my phone if there isn't enough internal memory)?

3)will there be any (real) performance improvement if we update apps? 

I know that certain updates provide new features,bug fixes(i hope it means errors) and change in the background/layout.Without considering the added feature,bugfixes and layout is it necessary to update?Also each update takes a good amount of internal memory in my phone as well as a lot of valuable mobile data.
If you use Mobile Data for update purposes, then it is better to update Google services and the messaging services only, but if you have access to WiFi then keep your apps updated.


Battery Optimization: There's a reason developers constantly update apps, and most of the time it's memory or battery optimization. Keeping your apps updated also means you have the best optimizations available. Likewise, delete old apps you no longer use, because these may be running background processes that chew up RAM and battery life.
Memory: The updated apps generally use memory efficiently in most of cases, though I don't think there would be much impact due to it. You can clear the caches or use softwares like 360 Security or Turbo Cleaner for that purpose.
Performance: Not always, but most of the time there is a improvement.


Stability: New versions of software also fix other, non-security-related bugs. For example, a new version could solve crashes you may be experiencing or make a feature work properly.