If you find yourself encountering this problem, it means that you are lacking memory or space in your device. In most cases, this problems occurs on Android devices since they have multiple memory and partitions unlike Apple devices which have one solid storage for everything. Depending on the device manufacturer or OEM for Android, some has Phone Storage, Internal and External Storage/Memory.
- Phone Storage means the space for free memory occupied by the operating system and some low memory consumption files such cache, temporary files etc.
- Internal Memory is a lot more bigger space in theory than Phone Storage or Memory. Some manufacturer does not have a Phone storage or an Internal Storage. They can be the same since most of them are only in partition. Basically, Internal Memory is the default path for installing applications, which in some cases Phone Memory can be the default if there is no Internal Memory allocation.
- External Memory or the so called memory cards and the like. It is detachable or optional storage/memory which the user can use. It can store all sort of files and application if allowed by the developers. Some applications does not work on External Memory which leads to the case that some of them are stored forcefully on the device's Internal or Phone memory which may also lead to lack of memory or free space. If the device manufacturer permits you can set External Memory as the direct installation path for all new applications if legible.
With the given information indicated above, most problem for Android lack of free memory is due to the Phone or Internal's memory low capacity. It is best advise that you delete some files or applications first depending on your default installation path. If you still have enough space in your External Memory then it is best advise that you transfer some of your data and files in it. They key is to have enough free space, so be sure to check the application or the game's spec requirement including the total or estimated memory consumption.
Please be reminded the Google Nexus line follows the same ideology on memory of having one storage for all, which may prevent cases like this and avoid any misinterpretation or confusion to end-user side.