When we think of a device of the enemy it is easy for drug abuse, alcohol, pills and things along those lines to come to mind first but this is where the subtlety comes into play because there are also devices just as destructive but they appear to be good.
Anything you cannot do without for a long period of time becomes a device, for example an obsession for a particular type of food becomes a device because you have to get it, and consume it so much that your body becomes overdosed with the ingredients of that particular dish or food item and you can now run the risk of becoming sick because of that imbalance, yet still you are going after it. The reason you need it is because your body has become trained to depend on this intake so you crave whatever it is.
A particular type of music or television show can be a device also because you may depend on it to relax, not realizing that you need to also be able to relax on your own. It is not bad to have things to connect with but it becomes dangerous when you depend solely on them for comfort, it is unhealthy especially when we know that before the production of certain songs and television shows rituals are being done to capture your mind in a particular way, which can also give entrance to certain ungodly spirits. In the literal sense televisions, radios and phones are called electronic devices, this is not coincidental.
Anything that you desire in a desperate manner can be considered as a device and if it is not adding to your spiritual growth it is an easy calculation to note, it is a device of this world, a device of the enemy because we are not supposed to be too hung up on any particular thing that we freak out if it is not made available to us. Money can also be made a device; it all depends on how you treat it.
On the other hand everyone has things they like to do which we know as hobbies, a passion that you may indulge in wholeheartedly from time to time which is absolutely healthy, however, from the moment it becomes an obsession then it can be deemed a device.
The word of God reads 1 Timothy 6:7, “For we brought nothing into this world, and it is certain we can carry nothing out”, so don’t allow anything to grab hold of you in such a manner, instead exercise self discipline at all times in every area and aspect of your life.
Blessings !