The modern convenience of iPads and other tablet computers is great. It provides a larger screen than a smartphone for easier viewing and it's far more portable than a laptop. Ideally, if you had to check your email, you wouldn't pull out a laptop, boot it up and say "give me a second". With tablet computers and smart devices we can surf the web and access important information on the go like never before. However, everything has a trade-off and there is finally research that suggests using these devices can cause neck, back, and shoulder pain if the user is not aware of their posture. Specifically, hunching over with the device on the lap, or being held in hand at a low angle for an extended period of time will usually cause a person to flex their neck, upper back, and shoulders. These flexion postures can cause pain and if left untreated over time, it can become debilitating.

Source