2016 05-07 amro handy labs workshop Gaza Sky Geeks

1. Handy Labs Apps and the
Technology Behind Them
Amro A Younes

2. Agenda
 Inspiration behind iOS App development
 Pocket Change
 uClimate SF
 iOnTime
 Observations

3. Inspiration and Beginnings
 Friend wanted to collaborate with me on his ideas, so we decided to take a course
together
 I wanted to learn something new
 Took the self learning Stanford iOS App Development course in 2013. Followed
the curriculum, completed all homework assignments, and extra credit
 Pocket Change was my final project.
 Used ARC to get a feel for memory management, despite auto memory
management already available in iOS.
 retain, release, autorelease
 Drawbacks, no one to grade my work and show me better ways of doing
something.

4. Why HANDY Labs LLC
 Patent Trolls
 http://www.thisamericanlife.org/radio-archives/episode/441/when-patents-attack?rgp-
redirect-tag=rgp-redirect-tag
 Liability Protection

5. Pocket Change
 Simple expense tracking tool for tracking cash incidentals
 Idea is not novel or unique.
 No app is as simple as this. Expense tracking apps contain budgets, graphs with no
easy interface to quickly enter your expenses.
 Initially marketed to folks who want to track cash incidentals only
 I personally found it more useful when I travel and marketed it as such
 The heart of the solution is CoreData, a.k.a as SQLLite
 iOS 6.1

9. Pocket Change

10.  Never hard code your values.
 Load from a text file:
 NSString *path = [[NSBundle mainBundle] pathForResource:@"categorywords"
ofType:@"txt"];
 NSDictionary *categories = [NSDictionary dictionaryWithContentsOfFile:path];
 Translate Dictionary to CoreDB
 CoreDB is not thread safe. Luckily access to it is quick. So always access it
from the main thread.
 Usually that is UIManagedDocument, or
[context performBlock:^{
// do stuff with context
}];
 Some contexts including Core Data ones have a parentContext. The
parentContext will almost always have its own thread, so you can performBlock
on it. But it is a different context, so you will have to save and then refetch to
see the changes

11. uClimate San Francisco
 Many areas in California have vastly different weather conditions. San Francisco in
particular
 Need a data source: Weather Underground
 Weather Apps are almost always free
 Extensible to any place with data points
 Hub and Spoke Architecture
 iOS 6.1
 CoreData
 iAd Framework
 MapKit
 UIKit
 CoreGraphics

12. uClimate San Francisco
Weather
Underground
uClimate
Backend
Server

21. uClimate SF Filtering Out Annotations

22. uClimate SF: Customizing Annotations

23. uClimate SF: Customizing Annotations

24. uClimate San Francisco
 Weather stations come and go.
 Updating configuration should not involve a new software revision.
 Every 24 hours back end server discovers new stations and purges old stations that
have not been active for a while.
 App requests weather station list from back end and updates its configuration on
the fly.
 App also processes custom list of stations. Updates are in the backend
 Multi-threaded solution to account for slow networks and prevent the UI from
locking up.
 Save and re-fetch approach in the DB is required due to different threads accessing
weather data.

25. iOnTime
 I live in a congested area. Your timing is highly dependent on traffic.
 I had the idea in 2013 but had to wait for iOS 7 so I could implement my solution
 calculateETAWithCompletionHandler: Available in iOS 7.0 and later, or use
 Google API
 Considered patenting the idea, but …
 Did not want to to store any date to address privacy concerns and not have to
manage out of sync information

26. iOnTime cont’d
 Had to wait for iOS9 so I could add public transportation
 Initially based on iOS7 then moved to iOS8
 MessageUI
 Foundation
 UiKit
 CoreLocation
 MapKit
 EventKit
 EventKitUI
 Apple introduced a similar concept a year after I started selling this App. Theirs is
built into the Calendar, it doesn’t work reliably

30. uClimateSF Texting
• If the calendar event has an invitee,
the App uses the contact’s mobile
number to auto fill in the To
• A preloaded message of I am on my
way is put together if leaving on time.
• If it detects you have not left it
autofills with: Running late, see you
soon.

34. iOnTime Design Considerations
 Minimize impact on battery when tracking location
 While in the foreground, implemented high accuracy GPS location.
 While in the background, woke up once a minute and updated my GPS location
 Minimize network usage by only requesting new travel time estimates every n minutes
or x distance since last location update
 Getting Apple to approve location tracking while running in the background took
months of going back and forth.
 The following plist configuration was rejected because they did not consider iOnTime a
navigation based solution
 Without the ability to run in the background, I was unable to use the most accurate
location based solution, or wake up to ask for location.

35. iOnTime Design Considerations
 Reworked implementation and background manager to receive significant location
updates from Apple
 The significant-change location service delivers updates only when there has been
a significant change in the device’s location, such as 500 meters or more.
 Updates to a change in traffic conditions changes are missed while in background
without location changes.
 Apple time estimates are okay. It would be great to correlate with other sources
such as Waze and Google Maps
 Remember ARC and auto memory management. Calendar event notification
expired as information was sent into the bowels of the App. Had to copy
information
 Multi-threaded to not lock up the UI while location and time estimates are derived.
 Dictionary of Dictionaries is a pain in Objective C. Easier in Java, and a piece of
cake in Python.

37. iOnTime Usability
Improvements
• Ability to filter out calendars
• Customize alerting
• Arrive a number of minutes before
appointment
• Receive alerts a number of minutes
before you have to be on your way
• Did not use CoreData
• Dictionary of Dictionaries to reflect
Calendar configuration is more
challenging than having done that in
CoreData

38. Observations
 Engineering is the easiest part of the App cycle
 Marketing your app and getting it to stand out amongst the noise is hard
 There are two forms of App development approaches, which one is you?
 You have an idea, its unique, or you can do better, faster, or make it more user friendly
 You have a business idea, the mobile app is your platform
 User Experience is key
 Do not do this alone
 Requires dedicated time due to frequency of OS updates, new languages
introduced, and new platforms.

40. Observations cont’d
 Take your app to the next level. Social interaction amongst users. Requires a
backend infrastructure to connect everyone.
 Careful with services like Parse. Very easy to use. Does not scale cost wise.
 Cheaper to build your own infrastructure but takes longer to develop
 Amazon Web Services
 Database such as mySQL, Mongo DB, HBASE (Big Data).
 Tutorial on Parse
 https://www.raywenderlich.com/15916/how-to-synchronize-core-data-with-a-web-
service-part-1
 Comparison of different services, Parse vs Stackmob vs. Appcelerator
 http://www.raywenderlich.com/20482/how-to-choose-the-best-backend-provider-for-
your-ios-app-parse-vs-stackmob-vs-appcelerator-cloud-and-more

42. Observations cont’d
 Monetization is not easy
 Advertisement model only works for apps that are engaging on screen
 People do not want to pay for apps. Less so on Android than iOS
 User retention gives value that you can demonstrate to investors
 In app purchases. Typical gaming model. Does not work for all paradigms unless your idea
lends itself to that concept. Celebrity apps do this as well.
 If you own data that you can provide an API for, you are in a very good place.
 Explored making demo apps that can be upgraded to paid apps. Had minimal
conversion success
 Tutorial on how to Market and Promote your App
 http://www.raywenderlich.com/11359/how-to-market-and-promote-your-games-and-apps-
part-1