Best credit cards available right now?

Amex Blue Preferred

6% on groceries
3% on gas
1% on everything else

and you get a $200 sign on bonus after spending $1,000 in the first 3 months

The Amex Blue Preferred as one of above posters mentioned for groceries (and you can buy gift cards at the grocery at 6% back, limited to a certain amount of spending a year)

Also, there's a ton of companies that have rotating 5% back categories. You can find a couple different offerings that give 5% back on gas

As for general spending that doesn't fit into a category above, there's the Citi Double Cash card that's 2% back on everything. There's also the USAA Limitless Rewards that's 2.5% back on everything, but you have to be a member and have at least $1,000 direct deposited into an account every month.

There's a lot of good travel rewards cards too, but I don't travel enough to have one. Some other posters on here can advise on those.

Also, if multiple places offer the same kind of card, such as the 5% rotating categories, see which one has the better sign-up bonus. There's several that'll give you $500 for spending X amount in 3 months

ETA: Re-read OP and noticed the 12 month no interest part. Don't know if any of the above offer that, but you can check. They might have low introductory rates. Usually a card either has good interest rates, or good rewards, not both. Might want to consider getting more than one card: one with good rewards for expenditures you can pay back each month + a second one for stuff you need longer to pay back.