Pricing schemes for text messaging have also contributed to the popularity of texting for spammers, said Conway. Because it's a lot easier to get an unlimited texting plan, he explained, a spammer can buy a bunch of SIM cards, put them in a box and start war dialing text messages.
"If you're not paying by the text message, if you're on an unlimited plan, that becomes much more cost effective for the spammer," he said.
Will SMS spam get as bad as email spam in its heyday? "I don't believe it will get as bad as email spam at its worst," Conway said. "I do suspect that it will get worse before it gets better."
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