While a staple of modern thriller and spy movies, burn phones are a “work around” to the SIGINT threats that cell phones pose against advanced and professional capable threats.
The concept is simple. Use burn phones between members that can not be tied to those people if analysis is performed.
The execution is hardly simple.
Most burn phones are “pay as you go” meaning there is a phone card, or the phone gets “topped up” on usage minutes so no checking or credit card account has to be used. Many pay as you go phones need a one time credit card payment to activate the account or top up, so a pre-paid Visa gift card or something similar is the tool of choice.
Because prepaid phones and gift cards are often sold at stores that record surveillance footage, so care must be taken when acquiring them. Also, if one phone becomes flagged other phones from that same store, or gift cards from the same store will also be watched, so best practice is to get a prepaid gift card from one store, Wait several weeks, then get a phone from another store.
Remember proximity analysis! If your “normal” cell phone was in close proximity to where either the burn phone, or the gift card were bought, it will be scrutinized more. Likewise, if a burn phone was ever in close proximity to your home, work, or any place you frequent, you will receive more scrutiny.
Remember link analysis! If you use the burn phone to call home, or friends or co-workers, or team mates, they will all be looked at more closely. A burn phone should only be used to call other burn phones, or call decoy numbers that can not be associated with you.
Remember pattern analysis! Your “normal” phone needs an alibi, or to be in its normal pattern. While inconvenient, start leaving your “normal” phone at home one day a week, or on weekends, etc, this creates patterns, that once established, are less likely to raise red flags.