What is the cheapest iOS device for gaming?

I'm planning to buy an iOS device in the Philippines for the sole purpose of GAMING. I've been seeing too many great games for iOS and I want to buy one.
What is generally the cheapest iOS device that is good for gaming.
Note: I have no IDEA about iOS devices, so please excuse me if I'm asking a stupid sounding question

What I need:
1.capable of playing most games with HIGH spec requirement.
2. NO LAG in playing a game with high spec requirement.

What I DON't need:
1.big screen.
2. Texting. (i mentioned it in case iTouch/iPod can play games instead of iPhone)
3. Any NON-GAMING app

Basically, if the a mere iPod/iTouch can play games with high spec in the app store without LAG, then I will go for it. IF there at least 1/4 of the games on appstore that can only be played at the latest iPhone/iPad, then I think I will save more to buy that.

I hope I'm clear on what I'm asking and I hope it's an easy question for iOS gamers out there. Thanks in advance.

Added (1). IF you are in the Philippines or has researched a pricing list, kindly provide one.thanks.

Added (2). If you are an IOS gamer, can you also tell me what iOS device you are gaming on? And how much do you recommend something?

The cheapest and best ios device that is for you is the iPod Touch 5th Generation or/and the iPad Mini.iTouch is thin, light, fast and almost no lags at all. Previous versions however lags A LOT. I'm not sure about the battery life if its enough for you but the iPad Mini sure would. For me, The screen size of the iPad Mini(7.9 inch) is the perfect size for a small tablet. 7 inch tablets looks too small for me. Many apps in iPhone/iTouch though aren't available in iPad.

iPod Touch 5th Generation & iPad Mini. It's your choice.

iTouch 5 - P12, 490, P16, 490, P21, 490
iPad Mini - P15, 990, P20, 990, P25, 990