Sue, I have just had an experience akin to what you might experience. Changing from iOS to Android. This is a cautionary tale:
This was not a choice thing, I found myself in Bali, Indonesia for an extended time with a failed iPhone. One day it worked and the next day it did not. I wont go into the boring details but suffice to say everything was tried to no avail, the thing was bricked.
So, what to do? Fork out an inflated price for a new iPhone (about 20% more than Australia) or purchase a popular local Android make.
The Samsung Galaxy is almost as expensive as an iPhone there, at least for the better models with comparable storage (the 5s had 64Gb).
So thinking that all Android phone were essentially created equal I bought a Vivo Y55 dual SIM with 16Gb storage. It was on special at around AU $200.00 plus a 32Gb expansion card came to a total of about $250.00.
My first mistake was assuming all Android phones were the same.
The Vivo while currently running 6.0.1 (Marshmallow) uses the FunTouch OS.
Unfortunately this OS is unable to "Adopt" an SD card so it cannot add it to the total system memory. Only a few apps are capable of changing their storage location to the SD card but fortunately they are the big two, pictures and music, but only with some serious fiddling ie moving the DCIM folder to the SD card.
I have had to change most of the native apps. They were the most basic versions imaginable. eg. I could not even Copy an Paste in the generic Contacts app. This required a lot of shopping, reading and trial and error as you can imagine.
I now have a satisfactory email app, contacts app, camera app, calendar, anti-virus app (essential on Android) and a range of other must haves such as MS Word, One Drive, Drop Box, and Mute an app thats makes all the noises and alerts this phone likes to make shut up so I can leave it on over night and a few banking apps.
So far, despite not being able to remove any native apps I found that you can delete their data so I still have 5.68Gb available on the phone and 26.4Gb on the SD card.
This whole process took nearly 2 weeks.
Because I have a MacBook Pro I also needed to find a successful means of data transfer and to date have only found two free and basically successful cross platform apps to achieve this. Android File Transfer (Mac OSX) and FileDrop (cross platform WiFi Transfer). This despite Android File Transfer requiring some tweaking of Developer Options on the phone, accessed in an almost mystical way. You have to go to Settings > More Settings > Software version > tap 7 times and Developer Options are added to the bottom of the previous screen (more settings). You also get a scary popup warning about the dangers of what you have done. It was essential however to Debug the USB connection to allow the phone to do more than just charge the battery via USB to the Mac.
So I have learned a lot about Android phones, settings, Android apps, the FunTouch OS and transferring macOS data. It has been a steep learning curve but I am now happy with this phone. I forgot to mention it's bigger than the 5s with a 35 cm screen and the added realestate, which I used to think was a bit ostentatious, is great for almost everything.
Oh, and one more thing, the battery life is double that of the 5s. I have a couple of times gone 2 days without charging.
I do not mean to suggest that my experience would be universal. No doubt other makes (OS's) would have different capabilities and limitations and I have to say my experience has been interesting and fun at times. I am no longer locked in to a "closed ecosystem" and a lot more could be written about that.
