For affiliate marketing, these people will need to be online a lot... they'll need to generate traffic through one means or another.
There shouldn't be an issue of safety, as long as they understand basic security (which most people don't).
- Old Phones: if they're using a very old phone, instead of a newer phone or a pc, they probably won't be able to do security patches on the system. Even if you jailbreak a phone, and install your own OS, you can't install a non-google version of android that will take security updates if the phone is more than a few years old... not unless you're a pretty serious phone guru.
- If they're in a desperate situation, they could always start with an unsecured system... but as soon as they start making money, or connect to any kind of bank, they're really at high risk.
(FYI, the criminals in poor countries get around this issue because they're usually working with stolen credit cards and stolen money... so they can either buy good equipment, or they just don't care about security for a while, since they're working with stolen/scammed money. But honest people, dong actual honest work, need to be more careful.)
So they'll need to learn/implement basic security (easy if they have an updatable phone or pc), and they'll have to be online a lot to generate traffic.
It's not rocket science, but money doesn't grow on trees, not even online.... they'll have to put in some effort.
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