Is 100mb a month enough for an iPhone 4s?

I don't have an iPhone right now, but I see a good plan for $43/month for a 4s with Unlimited texting, pic & video messages, and 100mb a month. My house, my school, and most of the places I'd be "browsing" (like buses, malls and fast-food places) have Wi-fi, so I'd be able to use it. I'd mostly be using twitter, and occasionally checking a couple other websites. Would 100mb be enough?

Right now, I have a really old Blackberry (from 2009) that costs $65 a month. It has unlimited internet and other features since it doesn't have a Wi-fi option

Added (1). I never travel anywhere either, so that won't be a problem, lol.

Yeah. That's good. I have a gig and only use about 50mb. Have Wi-Fi. My school wife sucks so I use data. Just maybe on trips look out abit.

  • Will 1GB of data a month be enough for an iPhone? I'm thinking of getting an iPhone, but only the small plan, which has only 1GB of data a month. The only thing I go on the internet for on my phone is Facebook. Will it be enough data? Or will it be constantly looking for updates and stuff and use internet data? My old phone did that and took away heaps.
  • Will 100mb of data be enough for a iphone 4s? The apps I would be using with data are just twitter and instagram. No emails, no streaming videos or anything and Wi-Fi would be used at home so would that be enough data for a month? I don't tweet a lot, just refresh twitter very often.
  • Is a 100MB or a 200MB data plan for an iPhone 4s better? I have Wi-Fi at home and I'm home about 70% of the time. I know I won't be using a lot of data, just some for Instagram, Tumblr, and Twitter when I'm not home. But I don't know how long 100MB will last me and how much/often I'd be able to use it when I'm not connected to Wi-Fi. So is 100MB good enough or should I go with 200MB?
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