Phones now have a "simulted SD card" as part of internal storage (I have no idea where that idea came from, but it wasn't this side of clever). Since LG has no external SD card you're stuck with what's there. (They also don't have removable batteries, so if the phone ever takes a dunking, you can start thinking of which phone you're getting next. And if the battery starts getting hot fast, throw it far away - a lithium explosion is very serious.)
However, even if you could add an external card, that's for data storage - pictures, videos, music, etc. Even programs that allow parts of themselves to be stored in external storage have to have parts left on nternal storage, so it doesn't save much space.
You buy a phone based on a few things, and in this order:
1) The carrier. The greatest phone, in an area where the carrier has no coverage, is a paperweight. Choose the carrier first. They have to have good or better coverage where you work, shop, live, go to school and spend most of your time.
(My last carrier, when I moved, had great coverage all over the city - even places I'd never go - but at my daughter's house, there was one upstairs window that kinda-sorta had coverage in one corner of one pane - if the phone was held horizontally. [I know exactly why her house doesn't get coverage, and they're not erecting a tower for one house and 55 acres of deer and squirrels.] Inside the front door, no signal. Step outside and down 2 steps and 4 bars and no problem. And it's not the house construction, it's the location of their tower and the location of a mountain ridge. I changed carriers.)
2) The features/storage you need. If you're a professional photographer, a great camera is more important than 450 apps. If you're a network administrator the camera is a nice thing to have, but you may never use it, so why spend more for better one?
But never buy a camera that doesn't have enough internal storage for the apps and data you think you'll need. The manufacturers count on your saving $50 on a camera this year, only to have to buy another one next year because that $50 savings cost you so much storage that the phone is now useless to you.
The choice of carrier, of course, limits your phone choices.
Now that you know which phones will meet your needs and work on your carrier, your budget will decide. (The cheapest phone that will meet your needs is always going to cost more than your budget will allow, so be ready for that. But giving up storage or RAM to save a few bucks is costly when you have to replace the phone in a few months. Watch TV instead of going to a show for a few weeks to make up the difference and get the phone you'll be happy with for a few years.)
