The most common cause for repeated iPad crashes is an insufficient amount of memory, also known as RAM. Older iPad’s have less RAM than newer models, which means they are less capable of running newer, system-intensive programs that require more RAM.
Each new version of the iPad features numerous technical improvements, such as an increased amount of RAM. According to Apartment Therapy, the first generation iPad had 256 MB of RAM, while the second generation had double that amount. When an app is opened, it uses the machine's internal memory to store temporary data related to the app. The crashes occur when the app requires more memory than the iPad is physically capable of providing. This overloads the operating system’s ability to properly function, causing it to crash and forcing a system restart. Due to the way Apple designed the iPad, it is not possible to upgrade the physical memory in any generation.
Some ways to increase the amount of available RAM are to regularly close all open apps. Once they are closed, the iPad no longer needs to store data related to them in the memory. Shutting down the iPad from time to time also helps to free up available RAM.