1.) SMS/MMS -These use your mobile carrier's cellular network and are hosted on their servers to route them and store them when you are offline. They do not use WiFi. These work globally across all carriers. Depending on your cellular carrier and your cellular plan you may or may not be charged for each simple text (SMS) or muti-media text (MMS). Each cellular carrier has their own size limit and these limits usually range from 600kb to 1,200k(1.2MB) and each carrier may or may not require cellular data be turned on. XM requires cellular data be turned on for MMS and charges you for the cellular data used. The XM size limit for an MMS is 600kb.
2.) Advanced Messaging - These are apps/features such as iMessage (Apple), RCS (Google Messages), Samsung Messages, and Verizon Messanger which give users the ability to send larger messages, with or without pictures, videos, or audio files over WiFi or cellular data. These messages are hosted by Apple, Google, Samsung, and Verizon. They only work between users who have enabled advance messaging and between users within each platform, however, if you send a message to a user on a different platform your software will attempt to send the message as an SMS or MMS over your cellular carrier if you have enabled it.
3.) Cross-Platform Messaging - These are apps such as WhatsApp, Facebook Messenger, Viber, and others. They are data only and only work between users with accounts on each App. They only use the Internet, and use WiFi or cellular data.
Mostproblems occur when users have incorrectly enabled an advanced messaging platform, or switch phones from one platform to another.
SMS stands for Short Message Service and is the most widely used type of text messaging. With a SMS, you can send a message of up to 160 characters to another device on a cellular network, It does not use WiFi.
MMS stands for Multimedia Messaging Service – essentially mobile messaging for pictures, sound and video clips. ... However, since MMS messages use an internet connection, you will need a cellular data plan to send MMS messages and will not be able to send MMS messages via Wifi.
iMessage is Apple's own instant messaging service that sends messages over the Internet, using either your cellular data or WiFi. ... iMessages only work between iPhones (and other Apple devices such as iPads) that have activated it. If you are using an iPhone and you send a message to a friend on Android, it will be sent as a SMS message and will be green.
RCS is Google’s own instant messaging service and works similar to iMessage except that it only works between Android phones that have activated it.
Samsung Messages has similar features for Samsung phones