My first one was a Samsung Galaxy S1 that I got in 2013 and it was a great little device that was easy to open up and repair. It had only 512MB of RAM but that was plenty for basic phone needs, web browsing and running some Android apps like AnkiDroid at the time.
Also a HTC Magic, that I bought on release day. Remember the excitement of flashing CyanogenMod on it with TWRP