Question you should ask your self
1. What are my memory requirements?
Do you need lot of memory (Not physical it is in heap) to process data or it is minimum? Now a day’s most of devices come with 64 MB heap size but this varies from Manufactures to manufactures. Even for same API level it is different. Find out your minimum and then make sure you have that amount heap memory available.
To monitor memory you are consuming at runtime check this
to find out how much heap memory available on current device check this and this.
Remember android is not like windows and every app start with same amount of heap memory, and it is constant for every app on that device. That means apps are not allowed to grow beyond this available memory. You can request for extra memory by this tag in manifest android:largeHeap="true"
but this feature is not available for pre 3.0 OS version .
I have try this application in one of the mobile where almost all memory are used by some other application. There my application not able to capture photo. And when I remove some application then my application work fine.
Above assumption is quite confusing because, when your app running Android put all other app side that means your app will have memory defined by you heap size, and if OS thought it needed more memory or failed to allocate more it would kill those process. Android give high priority to the task currently running. So if you are interacting with an app it highly unlikely that it will have less memory then heap size. their could some different reason for having trouble with other apps.
2. What are my API requirements?
If you are using any special API which is not available to older API and level then, you have two options either you say you app simply not going to support that API version or you can back port that specific feature.
3. What are my hardware requirements?
Ask yourself if you are using any specialty software or hardware, if that special hard available to all devices or not? Example, NFC, bluetooth.
4. What are my display requirements? Is this app only for mobile or for both mobile and tablet? What about those 7 inch which fall in-between tablet and mobile.
5. What are my localization requirements?
Is this app relying on any special character set? What if a certain device do not have those characters.
And, FYI amount of object you mentioned that should not occupied more then few MB. But careful when working with bitmap. Read this