Can we use a smartphone without battery?

Can you run your smartphone without a battery like you can run a laptop by directly plugging in? Know from our technical experts if it possible and if not, why not?

Nowadays we are using smartphones in various designs, categories, and specifications and accordingly they are having price difference also. Battery is the crucial part of these phones. I have observed that in many brands especially at lower and middle segments sometimes the batteries are going bad and the original battery is not easily available in the market. Due to this many users are going for a new phone which is of course a costly proposition. I had a laptop which I used without battery (as the battery went bad soon) by plugging it on the mains comfortably for 3-4 years. Of course I did not need to take it out also as I am a retired person. From the same analogy I was just thinking whether we can use our smartphone also plugged to its charger or some other means to connect it to the 4 to 4.5 Volt DC power supply. I understand that in that case it loses its mobility but just thinking theoretically, is it possible? Is anyone having experience in this regard?