New iOS blackjack app shows you EVs in real time, plus more stuff

Hi guys,

I made a blackjack app for the iPhone/iPad which was approved by Apple last night:

https://itunes.apple.com/us/app/blackjack-x/id895288053?mt=8

It has a lot of features that I think would be very interesting to you guys, e.g.:

- It can show you EVs in real-time as you play (based on a fresh shoe AND the actual shoe if you unlock the Ultimate version)
- The Ultimate version has a "hand analyzer" feature which you can use to quickly type in scenarios and see corresponding EVs
- The Shoe menu (Pro version) does a Monte Carlo simulation using the current cards in the shoe to show you the (approximate) EV of... well, betting
- There's an "Analyze your play" feature that lists the hands you've misplayed (according to basic strategy) and how much each "mistake" would cost you, on average
- I calculated Basic Strategy for 6700+ rule variations (took over 12 hours of compute time in the cloud) and the app includes this database, so you can change the rules around and then see/email/print the corresponding strategy card immediately

Plus there are some features I think are helpful for learning basic strategy, like flash cards, but I imagine they wouldn't be so interesting to this crowd.

Anyway, I have seen several threads on this forum with people discussing EVs of various situation and asking for basic strategy for various rules, so I think this app could be pretty interesting if you're curious about that stuff.

Feel free to ask any questions you might have about the app! I have tried to make it interesting and valuable for enthusiasts and would certainly appreciate feedback or discussion.

It looks pretty cool. Obviously most of the useful things are locked to upgrades =). I like the Layout/Menu/App all together. From a programmers point of view I think it would be easier to have dropdown boxes for a few things rather than textboxes. Anytime you can control user input, you should =p. Also, it might be easier to change your bet if you simply had 3 chips (red, green, and black - or actually red, green, and an X image to clear the bet) above the stack that is your BankRoll. Clicking those could increment your bet by that amount. Obviously you would also need some kind of clearing button/image.

I also noticed when a player busts, the dealer still plays their hand out, drawing more cards. This is not typical in the U.S. I don't know if this was intentional or not but should be pretty easy to fix with a simple check.

Questions:

1) Do you plan to have an update where you can play more than one hand? As shown by Wong it's actually best to play no more than 2 hands, so perhaps you'd only have to add a spot for one additional hand?

2) In the Statistics Menu how exactly are you calculating the Observed Value?

3) Just to re-iterate (since I can't see it on the free version) you said in the Ultimate Version you can actually see the EV numbers for each hands decision above their corresponding action button (hit, stand, split, double, surrender), correct?

4) Is there an option to set the deck penetration? Being this is one of the most important variables, I'd assume you could set it a little light/heavy pending your local casino's standards?

Great work! The app/animations are smooth and quick. I do wish I could play around with it a bit more. Could you perhaps provide some screenshots of the Pro and Ultimate version to actually see what these other functions look like?

Great, thanks for the feedback! To get this out of the way, here's the official web site for the app. It's not fancy but it does have a bunch of screen shots of the different features:

http://www.roamingtrek.com/blackjackx/

1. No, I don't expect to support multiple hands. That would have added a huge amount of complexity to the UI that I didn't want to get into.

2. The Observed Value is an average of your wins/losses per hand, normalized by dividing by your initial bet amount. So if you play one hand and get a blackjack, the OV is 1.5. :)

3. Yes, you can see from the screen shots on the web site (linked, above) that the EVs appear above the buttons as you are playing.

4. Yes, you can definitely set deck penetration to whatever you want, in the Rules menu (Decks submenu).

Hope this helps!

Fantastic, I wasn't sure if you had a site with images or not. I really like the EV's per playing decision. Now are those based off of the default counting system (hi-low I'm assuming)? Or are they based off of knowledge of all the cards being played?

E: As a programmer myself I can tell everyone else it looks like a good amount of effort went in to this app. I'm sure anyone of most levels could get $6 bucks worth out of it. Time to upgrade I think =).

There are two sets of EVs which I've attempted to explain in the help file in the menu (the menu option with the 'i' and the circle around it) and on the web site, but, briefly:

1) The color-coded EVs at the bottom with the underline are "fresh shoe" EVs which are calculated based on a full shoe, minus the cards that you can see on the screen, i.e., the dealer's up card and the cards in your hand(s).

2) The gray EVs above those are based on the actual revealed/hidden cards in the current shoe. So those are the "perfect" EVs that you could calculate if you were counting cards perfectly.

The EVs are (usually) calculated using an algorithm I came up with to enumerate and sum up all the necessary probabilities.

The obvious way to implement this algorithm would require hours of computing (on a desktop computer) to finish certain hands but I have come up with some optimizations so that it rarely takes more than half a second on a newer iPhone.

That being said, there are some cases where there are just too many probabilities to enumerate. Basically to do with splitting. That could easily take days to compute, even with optimizations. The "search tree" just explodes. So, to display those EVs I use Monte Carlo simulation and assume basic strategy for the current rule set.

Sound great. Congratulations. Work on something new and different for VP.

Sorry, haven't come across this acronym before. I'm familiar with AP -- Advantage Play. Is this what you're referring to?

Quote: motrek

Sorry, haven't come across this acronym before. I'm familiar with AP -- Advantage Play. Is this what you're referring to?

Video poker bur an all in one would be great including keeping track of wins losses, tips expenses etc etc. I would pay $50 for a good one.

Quote: AxelWolf

Video poker bur an all in one would be great including keeping track of wins losses, tips expenses etc etc. I would pay $50 for a good one.

Gotcha. Sorry, no plans for video poker. I have never played it myself so I don't think I have any special experience or insight or interest that would allow me to make a good app for it.

Quote: motrek

Gotcha. Sorry, no plans for video poker. I have never played it myself so I don't think I have any special experience or insight or interest that would allow me to make a good app for it.

How about something you can fully customize?

Quote: AxelWolf

How about something you can fully customize?

I read a little about video poker and don't think there's enough overlap between the games that you would be able to configure blackjack code to also work for video poker.

It might be kind of an interesting problem to do on a phone though because to calculate the EV of returning 5 cards you basically have to evaluate approx. 52^5 = 380M hands, or the entire game space. Naturally it ends up being less than that since the order of the cards don't matter, but that might be kind of hard to account for. :/

Since there are 32 possible decisions to make per hand, it would be a fairly easy matter to accumulate average payouts and probabilities for each one as you evaluate every possible hand, so you would be calculating the EV for all possible decisions at the same time.

But still, 380M is kind of a lot. I bet this would take more than a minute on a faster cell phone. I can't imagine you would want to wait a minute to see EVs. Probably there are ways to speed this up that I'm not accounting for since I've only through about this for a couple minutes.

BTW -- just did a search and found this app which seems to do exactly what you want already. :)

https://wizardofodds.com/apps/vpwizard/