AT & T suggests top data users use wi - fi to avoid reduced costs in future . The message alerts consumers that they are among AT & T 's top 5 % that billing period , and suggests they use Wi-Fi to avoid reduced data speeds in the future . AT & T was the first carrier to introduce the tiered data plan concept to customers . It introduced its unlimited data plan in July .
AT & T suggests top data users use wi - fi to avoid reduced costs in future . AT & T was the first carrier to introduce the tiered data plan concept to customers . It introduced its unlimited data plan in July .