I've been using the Airtbiz wallet on my iPhone to make gambling related transactions. I like Airbitz because you have total custody of your bitcoin and they don't track transactions so you can deposit at any sportsbook or casino without having to worry about them shutting your account. The wallet also dynamically calculates the correct fee when I want to make a transfer. It works pretty well most of the time and my transactions usually gets confirmed within 10 minutes but there have been a few occasions where it has taken over an hour. Which btc wallet has the best dynamic fee calculator for times when you simply have to get your transactions included in the next block?