Both are instant, and senders generally expect instant responses
Both are intrusive (messages pop up over other content) and used for informal communications
To Text...
Text messages are ubiquitous - nearly everyone can send and receive 1-to-1 text messages, and most can receive MMS (multimedia messenging service) message with multimedia content and multiple recipients. But SMS messages aren't secure. The How-To Geek identifies several reasons why SMS text messages aren't private or secure, including:
Your Cellular Carrier Can See Your SMS Messages
SMS Messages Can Be Intercepted by Criminals
SMS Messages Can Be Monitored by Authorities
Your Phone Number Is Surprisingly Easy to Hijack
Or Not to Text
A recent survey found over 90s of Americans actively used instant messengers (aka Chat Apps) in the 3rd quarter of 2020, beating social network apps like Facebook, MeWe and Minds. Twitter CEO Jack Dorsey recommended George Floyd protesters, who caused $1-2 billion in private property damages, move communications from Twitter to Signal, possibly to avoid a similar shutdown suffered by microblogging competitor Parler.
Secure Instant Messages offer advantages over SMS Text messages, including:
Many (but not all) IM options provide end-to-end encryption
Some also provide video chat, groups, and offer the ability to manage SMS text messages, too
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