Advise which bitcoin wallet is the best on your smartphone?
Mycelium, their features is almost(or probably) same as electrum.
You can also buy a cheap smartphone or a Raspberry Pi and use it as your hardware wallet
Agree, i use smartphone as my hardware wallet. As long as you didn't download or open any suspicious thing on your phone, then this one its a good choice.
The coinomi wallet is also a good choice for a mobile wallet never had any issue yet that is why I recommend this wallet the good thing here you can also save other cryptocurrencies.
If you use a smartphone make sure to don't use a clone smartphone because most of the clone phones are rooted so it can easily get hack but if you are using an orig phone like Samsung you are safe just don't root your phone.