Recently, while on vacation, I was pleasantly surprised to get an email from Wiley Publishing Inc saying that the iPhone Economy app had been selected to be featured in their book on Incredible iPhone Apps. This was great news.

The iPhone Economy app is one of the apps featured on the cover of the book. The app (which can be downloaded from here) is also featured in chapter 5 (which focuses on the “Finance” category of iPhone apps). In chapter 5, the book also features other great apps from the ”Finance” category and this includes apps from the big guys like Bloomberg, E-Trade etc. So it was great to see that the Economy app was chosen to represent (chapter 5,) the “Finance” category in the Table Of Contents of the book.

Incidentally, one of the author’s two feature requests for the app (landscape mode support for the graphs) has already been implemented for the app. His other feature suggestion was for the ability to see news stories/analysis relating to each economic indicator.

The author, Bob “Dr. Mac” LeVitus has done a great job of compiling a list of incredible apps for the book and writing up a description/commentary/review for each one of the apps.  He mentions that he spent several months on narrowing down the list, testing the apps, writing notes etc.  The author also mentions that he tried to talk his editors out of naming the book as ‘Incredible iPhone Apps for Dummies’, but that he couldn’t get them to drop the word ‘Dummies’ from the title. Regardless, it seems like a great book for anyone who has trouble wading through the 150,000+ apps in the iPhone app-store to find quality-apps.

Of course, I should add that Wiley Publishing sent me a complimentary copy of the book and I’d like to thank Wiley Publishing as well as the author for featuring the iPhone Economy app in their book. The book is available at http://www.amazon.com/dp/0470607548 , http://www.wiley.com/WileyCDA/WileyTitle/productCd-0470607548.html etc. and at book stores.

The iPhone Economy app provides a snapshot of the US economy. It was launched on July 4 and went on to become the #1 paid app in the “Finance” category of the app store.  The app was featured in Apple’s (itunes) STAFF FAVORITES section and also in the media.

The iPhone Economy is probably the first iPhone app to use Twitter OAuth to post tweets. From a development-resource perspective, the Twitter functionality was easily the most expensive component of the V2 upgrade. Most of these costs came from implementing login with Twitter’s new OAuth authentication protocol. Later in the post, I’ll write more about costs and about OAuth benefits of security and privacy. Adding Twitter functionality to the Economy app was first suggested to me by @hivebrain, but at the time, both of us had assumed that this would be a fairly inexpensive feature.

The app creates a community of Twitter users of the iPhone Economy app with the #cEconomy hashtag. It auto-generates economic tweets on the latest economic indicators (e.g. GDP, Unemployment, Housing starts, inflation etc.). The default tweet text includes latest numbers and how it compares with the past (as an example, today, my twitter post with default text showed the November unemployment rate (published today by the Federal Government) and compared it with last month’s rate and last year’s rate.

Users may choose to edit the default text and these tweets are suffixed with #CEconomy. Standard/unedited tweets are suffixed with #cEconomy. Tweets from the iPhone Economy app can be identified by the source of the app (which will say iPhone Economy app). All tweets from the app will have the cEconomy (or CEconomy) hashtag and a search on #cEconomy will return all tweets from the app.

An explicit user action (tap of the “Post” button) is always required for posting tweets.

OAuth, Security and Privacy

As mentioned earlier, implementing Twitter login with OAuth turned out to be fairly expensive (in terms of dev resources). The Twitter.com website recommends that all applications use the OAuth login approach “to prevent security issues” and says that the basic login approach will be deprecated in the future. However, at the moment, it looks like the iPhone Economy app is the only iPhone Twitter app that uses OAuth for login and posting tweets.

Apps that use basic login ask users for their password and typically save the password on the device. With basic auth and with oauth, a malicious app can compromise security, but with basic-auth, a non-malicious app may also compromise security. It is possible to write secure code with basic auth, but several developers don’t do that and OAuth mitigates these risks.  At least one popular iPhone app used to save an unencrypted password on the device. Presumably, some PC/Mac/iPhone apps send raw passwords over HTTP. Regardless of whether they save the password on the device or not, all apps that use basic login, directly ask the user for their passwords before handing it over to Twitter.

In contrast, the iPhone Economy app uses OAuth and so it doesn’t get or use or save your twitter password anywhere. You log into a twitter web-page, provide your password to Twitter (not to the app), and inform Twitter that you’re authorizing the iPhone Economy app to update your twitter data. Twitter then provides the iPhone Economy app with a token that permits it to make twitter posts on your behalf.
The iPhone Economy app saves this token securely on your device. The token cannot be read by anyone else. You can remove the token by tapping the ‘Logout’ button on the ‘Post to Twitter’ page. You also have the option of revoking authorization through the Twitter.com site (without using this app).

The authorization token is not a password and it cannot be used by anyone other than the iPhone Economy app. The Economy app uses the token when you explictly tap the ‘Post’ button on the ‘Post to Twitter’ page.

To encourage OAuth adoption in new apps, Twitter will only show the source of tweets (status updates), if the new app uses OAuth. However, tweets from old apps that use basic auth continue to show the source of tweets. The source of the tweet typically shows below the the tweet (as …From AppName)

Twitter OAuth has been available since March 2009. However, the biggest disadvantage of using OAuth login (as of now, December  2009) is that Twitter’s OAuth login page is not mobile-friendly and users see a login page that is formatted for a laptop/PC, not an iPhone. We have been working with Twitter (the company) on this and they’ve assured us that they will work to “improve the mobile oauth” experience. Until then, unfortunately, users may find the login UI a bit difficult to use. Of course, another disadvantage (from a developer perspective) is that implementing login with OAuth is expensive (from a development time perspective). However, overall, I hope that users appreciate the usage of OAuth login.

I also hope it is fun to tweet the latest economic news (even though the news itself may not always  be good)

1. By the end of August, around 90% of our users were on OS 3.0 (or later). The overwhelming majority of iPhone users were on OS 3.x, roughly 3 out of 4 iTouch users were on OS 3.x. By the time Economy 2.0 is released (mid October), we expect an even higher number of users to be on 3.x versions.  In itself, this was not a sufficient reason to be OS 3.0+ only, however, this was an important consideration.

2. Future versions of the Economy app will include iPhone OS 3.x only features such as in-app-purchase and in-app-email. Some of the iPhone OS 2.0 apis are being deprecated by Apple. For example, the “font” property of UIButtons has been deprecated and Apple recommends setting the  “font” property of the button’s “titleLabel”. However, titleLabels didn’t exist in any of the iPhone OS 2.x versions.

3. Apple’s policy on previous versions: Supporting iPhone OS 2.x (for old functionality) and yet using new iPhone OS 3.x features (that will only work on OS 3.0 or later updates) is possible, but it is somewhat expensive because of the testing hit. Specifically, as per http://support.apple.com/kb/TS1275, Apple says that “Downgrading to a previous version is not supported”. So it isn’t possible for us to move an OS 3.0 device to OS 2.x for test purposes. While it may be possible to borrow or buy an old iPhone with the 2.0 OS on it, this would exacerbate our time constraints and further delay release of the Economy 2.0 app.

4. The most important consideration was the fact that the 1.0 version of the Economy app is a high-quality app that offers great value. So I’m comfortable with a small minority of users continuing to the use the 1.0 version of the 99-cent Economy app and not picking up free upgrades with the 2.0 version.

(PS: Incidentally, the 1.1 version of our Election app was released last year and yet  our servers get some requests from the 1.0 version of the Election app; some users upgraded to the 1.1 version several months after release, some other users continue to use the 1.0 version. This indicates that some of the iPhone OS 2.x users of the Economy app will probably stick with the 1.0 version of the app, even if the 2.0 version of the app supported iPhone OS 2.x)

If you have any concerns or thoughts about not supporting iPhone OS 2.x, please email us or post your comment as a response to this blog post.

The iPhone Economy app was released on July 4 and it got to the 4th place (in “Finance” ) within a week after release. We have received a number of emails from users and most of them said they loved the app. Many (though not all) feature requests/suggestions from our users will be implemented in our 1.1 release. The 1.1 version is due to be released in the first half of August.

http://CascadeSoft.net/Economy.aspx has more details on the app and the app can be downloaded from the app store.

Incidentally, the iPhone Economy app is the 4th app from Cascade Software Corporation.

It is also the second #1 app from Cascade Software Corporation. Last year, our first app (the iPhone Election app) was – at one time – the #1 paid app in the “News” category.

http://CascadeSoft.net/Economy.aspx has more details on the app and the app can be downloaded from the app store.

It is one of the 8 featured apps on the first page of the “STAFF FAVORITES” section (in an app store that has more 65,000 apps)

The iPhone Economy app displays the latest values for several key economic indicators (e.g. housing, employment, trade deficit, inflation etc.) and draws graphs tracking the history of these indicators over the past few months, years and decades.

The app also compares the latest value of each indicator (e.g. housing starts) with its value from the previous month and the previous year. To make this comparison easy on the eye, we decided to add a green-up-arrow indicator if the latest value was more than the previous month’s value and a red-down-arrow if the value was lower than that of the previous month. See picture (at the bottom of this post) for an example of the UI.

Originally, this seemed like a good idea, but it raised a usability question. The app includes indicators like “unemployment rate”. Showing a green up-arrow for an increase in unemployment didn’t seem like a good idea because a green up-arrow would signify “good” to most people, but very few people would consider an increase in unemployment as good. So here are the options we considered

1. No arrow to indicate increase/decrease, just a sentence that mentioned the increase or decrease.
2. Using the same color to indicate increase and decrease (with an up arrow indicating increase and a down arrow indicating decrease)
3. Using a green up-arrow for indicating a “good” increase (like an increase for the GDP parameter) and using a red up-arrow for a “bad” increase (like an increase in the unemployment rate)
4. Using a green up-arrow for all increases and a red down-arrow for all decreases.

Option-1 seemed a bit user-unfriendly because it was limited to text. Option-2 was better, but using the same color meant that the up and down arrows were less easily distinguishable.

Option-3 had a couple of disadvantages. It introduced a minor inconsistency because some indicators would show increases with a green up-arrow and some others with a red up-arrow. More importantly, it introduced a judgmental element that wouldn’t necessarily be correct. For instance, is it “good” for the interest rate to go up or for imports to go up or for the dollar to become stronger? Arguably, sometimes it is good for some of these values to increase and sometimes it is good for these values to decrease. Option-3 also required some (minor) additional development work.

Given all of the factors discussed above, we decided to go with option-4 in spite of the usability question mentioned earlier. It will be interesting to find out whether users would have preferred one of the other options. However, as discussed in an earlier post on product design, startups need to make quick decisions and execute and ship quickly. So executing on option-4 was the best option for the app.

iPhone Economy app - results, top section

This app gives you a snapshot of the US economy with the latest values of several key economic indicators published by the Federal Reserve. It also provides interesting graphs with historical values of these indicators over the past few months, years and decades.

Details of the app are available at http://CascadeSoft.net/Economy.aspx and the app can be downloaded from the app store.

I also enjoyed reading the first review on iTunes. Here is what the reviewer said about the app.

‘Wow is this an eye-opener! No opinions here, just the facts. Straight information from the government’s own databases on who’s been getting federal contracts, and for what since 2000. You can look it up by department, by state or even by item – which makes for some very interesting browsing.
Try looking up ‘land mines’, for instance, and you’ll see a sharp escalation in 2008. What’s the story behind that ??

And that, in a nutshell, is what you get from this very handy app: the straight story on what the government has been buying with your tax dollars.  This is one reference app that will actually raise more questions than it answers – as well it should. Kudos to the developers for a nice job in putting this information into a format that’s easy (and fun) to explore.’

The app also got good TV coverage. Erik Sandoval (a news anchor for Northwest Cable News) discussed the app with me and he talked about the app on this week’s “Talkin tech” segment.

Check out the tv coverage on  http://www.nwcn.com/video/tech-index.html?nvid=357050 (our regional cable news network) or http://www.king5.com/video/?nvid=357050  (our local NBC affiliate). It is a short video.

The app is available in the app store. Writing the iPhone “Government Spending” app was a lot of fun and I’m glad that users are enjoying it. I’ll add another post with comments from the first review on iTunes.