ATT or Verizon

That one is hard. So many moving parts, and a lot of sales volume.
The things I can think of to consider are: technological advances consumer preferences applications data bandwidth call coverage extreme competition licensing
profit margin (separate category, always important, but predicting it is key).
The plus side of the analysis is that there is a lot written about each company and the industry. Short of reading that, Elle's comment is very practical. It's clear that cell-phones are not going away, and are expanding capabilities. When in doubt, watch the bottom line.
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