Remember about the private key that you need to move your Ethereum? This key is the Ethereum storage key. The person who has the key is Ethereum who controls Ethereum. This key can be a key in digital or physical format as written on a piece of paper.
I do not understand what your point of view. But, according the title of this thread I can understand what you mean.
If you want to make your Etherium wallet safe, you must keep your private key offline or write down on paper. Do not share your private key to someone else. If you use decentralized exchange, be careful. Some of them are not safe. Like etherdelta. I suggest you to avoid it. It's better to use Idex.
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Then, I recommend the trusted Etherium wallet, like Myetherwallet and metamask. Don't use Etherium android apps without any recommendation of trusted forum member. Keep your money safe, keep your assets safe.