OK So very GENERALLY
When we talk about Low Frequency ( LF ) we are GENERALLY talking about 125kHz and GENERALLY the T5577 chip, This is an amazing little chip can can emulae MANY different modes and it can also have its UID changed, but you need a specific reader/WRITER to do this, GENERALLY it will be a Proxmark 3 and GENERALLY it will be a PM3 Easy. 
There are othe LF reader/writers like the Blue cloner 
and the dreaded white cloner, plus some others.
When we talk about High Frequency ( HF ) we are talking about 13.56MHz, which conveniently your phone uses also with NFC, There are more HF chip options, because there only a few that have changeable UIDS (NUIDs), xM1, FlexM1 which are very common out in the wild, the FlexM1gen2 can have it’s NUID changed with a phone or PM3 but the others will require a PM3, the Magic Mifare M1 is a great chip but they cant emulate other chip types.
The FlexMN is a HF Magic chip that can have its UID changed, and can emulate a number of other HF chips excluding the Magic Mifare M1.
The MagicNTAG (FlexMN) can have the UID changed with both phone with shell commands and PM3, with the PM3 being the safer option of the two.
Where an HF chip has an unchangeable UID, to be able use this on a particular compatiable system, it requires the UID to be enrolled; This is easy when you own or have access to the system, and a little more difficult when you don’t, as it may require some social engineering of the system administrator to enroll it.
Most HF chips can have NDEF written to them and some like the xDF2, FlexDF and FlexDF2 etc can also have applets written to them.
I hope this helps to answer your question…