I own a MicroMax A100. I want to install the latest version of a different ROM (Samsung or Nexus).
Is it possible? If so, can you tell me how?
If not, can I install a ROM made for a different device, but from the same manufacturer? For example, could I install a ROM for the MicroMax A110, which is the successor of A100?
You can only install ROMs compatible with your device
Different Android devices use different hardware, which requires special drivers (e.g. the camera). Those drivers are sometimes/often proprietary (take e.g. Sony, which almost made it into the AOSP project -- but had difficulties due to those proprietary parts and thus had to back-out again: AOSP only allows for non-proprietary, Open Source code, like its name suggests: Android Open Source Project). Installing an incompatible ROM, in the best case, makes components of your device unavailable (they are simply not working). In the worst case, you might "brick" it (it won't even start up).
You might want to check the question Where can I find stock or custom ROMs for my Android device? to find ROMs compatible with your device. Most times, there are several choices available to meet the user's requirements: Less "bloatware" but more performance, more fancy stuff, custom enhancements... So you still can make your pick.
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