Building an Open Source iOS app: lessons learned Dec 12, 2016, Hacker Dojo (Santa Clara), 6pm In this talk I'm going to talk about lessons learned from building Sensorama (http://www.sensorama.org), an Open Source sensor platform for data science. The main theme of the talk will be Open Source: what is great about it, what is bad and how you must become a part of the Open Source community to really move quickly and benefit from it. For this project, I did both the code and the design, so you'll have a chance to see how solo-developer deals with time/feature constraints, which tools I've used and what my approach towards development in this mode is. In other words: I'll tell you what I did to stay sane. If the iOS development were a walk in a dark city park, this talk may turn out to be your flashlight. If you like it, star it at GitHub: https://github.com/wkoszek/sensorama-ios Agenda https://www.meetup.com/svmobiledev/events/235836893/ Materials https://github.com/wkoszek/talks/tree/master/svmobiledev2016 Some links from the slides Fake it till you make it presentation https://developer.apple.com/videos/play/wwdc2014/223 Designing for Future Hardware https://developer.apple.com/videos/play/wwdc2015/801/ References WWW: http://www.sensorama.org GitHub (code): https://github.com/wkoszek/sensorama-ios GitHub (artwork): https://github.com/wkoszek/sensorama-artwork Author WWW: http://www.koszek.com Twitter: https://twitter.com/wkoszek LinkedIn: https://www.linkedin.com/in/wkoszek/ Email: wojciech (at) koszek.com

1. Building An
Open-Source iOS App
Wojciech Adam Koszek · http://www.koszek.com · ! wkoszek
Silicon Valley Mobile Developers & Designers, Dec 12th, 2016

2. Building An
Open-Source iOS App
Wojciech Adam Koszek · http://www.koszek.com · ! wkoszek
Silicon Valley Mobile Developers & Designers, Dec 12th, 2016
EVERYTHING (opinions, thoughs,
feelings, projects) in this talk are my own
and NOT my employer

3. Today's talk is about
Sensorama
Open Source Sensor Platform for Data Science
http://www.sensorama.org

4. As I talk...

5. Visit website
http://www.sensorama.org

6. Install...
...on App Store

8. Quick Q/A
to the audience

9. Developers of
iOS or Android?

10. Favourite
Open Source?

11. Have you ever
Contributed to
the Open Source?

12. How many
Apps submitted
to the Apple or
Play Store?

13. Do you
Plan to publish
an App?

14. Do you
Plan to publish an
Open-Source
App?

15. My agenda

16. 6 parts
Questions and discussion
afterwards

17. 6 parts
Questions and discussion
afterwards
OK to interrupt and disagree!

18. Motivation
Why/how/who/what/when
Design & App Concept
First app look and feel
Usability tests
How people liked it?
Implementation
Which tools I've used and how I've used them.
Open Source: good and BAD parts
What to do and what NOT to do
Summary
Q/A

19. Motivation
Why/how/who/what/when
Design & App Concept
First app look and feel
Usability tests
How people liked it?
Implementation
Which tools I've used and how I've used them.
Open Source: good and BAD parts
What to do and what NOT to do
Summary
Q/A

20. Motivation
Why/how/who/what/when
Design & App Concept
First app look and feel
Usability tests
How people liked it?
Implementation
Which tools I've used and how I've used them.
Open Source: good and BAD parts
What to do and what NOT to do
Summary
Q/A

21. ...and convince you that
doing OSS development
is something your
should try

22. My background

23. Motivation
1

24. SETI...

25. ...for Sensors

26. Data science research

27. Data science research
Nice to be able to use your own data for your
education

28. "Product Manager"
Exercise

29. Dealing with users, their
feedback, design and look,
code, etc...

30. Real-world "app"
experience

31. Very different from
UNIX stuff I'm used to

32. Open-Source
Development Exercise

33. Open-Source
Development Exercise
Open code design, development and
maintenance done in GitHub

34. Making practical stuff is a
Great way to learn

35. From 0 to...

37. Design and
App concept
2

38. General idea

39. Sensor data recorder

40. Tap to start recording

41. Tap to stop recording

42. Easily export data out of
the phone

43. Just e-mail the file to the
user

44. Open data format

45. Open data format
Everyone can open and parse the
data

46. JSON

47. Looked at other similar apps
"Good artists borrow, great artists steal"

48. Voice
recorder
Recording interface

49. Apple's
Voice
Memos
Recording interface

50. Clock
Nice Table Views

51. WWDC
App
Nice Table Views

52. Podcast
App
Decent colors/views

53. Decided to use 3 screens
As simple as that!

57. Early prototypes

58. Paper is much better
Very easy way to iterate

59. No need to draw much
of complex stuff
Just rectangles, squares and circles

60. Picking tools?

61. Picking tools?
For Open-Source they must be
reproducible + automated

62. Started with designing in
InkScape

63. Started with designing in
InkScape
Android

64. Started with
designing in InkScape
Too much work for early design
Too few people use it to make it practical

65. Open Source: less
availability for design tools
There are some, but most of designers don't use them

66. Commercial tools:
much better for now

67. You probably already
have them

68. Keynote

69. Some design/prototyping inspiration Apple's
"Fake It Till You Make It"
WWDC presentation
https://developer.apple.com/videos/play/wwdc2014/223

70. Some design/prototyping inspiration Apple's
Designing for Future Hardware
WWDC presentation
https://developer.apple.com/videos/play/wwdc2015/801/

71. PowerPoint

72. Software I paid for

73. Affinity Designer

74. Affinity Designer
Not enough community yet. VERY promising

75. Affinity Designer
Not enough community yet. VERY promising
Flat rate pricing

76. Affinity Designer
Not enough community yet. VERY promising
Flat rate pricing ($50)
NO scripting yet....

77. Graphic

78. Graphic
(used to be iDraw)

79. Graphic
(used to be iDraw)
Nice and simple

80. Graphic
(used to be iDraw)
Nice and simple
Scriptable (uses http://jstalk.org/)
Powerful but WEIRD
No real ecosystem (templates, stencils)

81. Software I recommend

82. Adobe Creative Suite

83. Adobe Creative Suite
If $50/month is OK with you

84. Adobe Creative Suite
If $50/month is OK with you
All their tools work well within the
suite

85. Sketch

86. Sketch
Somewhat popular recently

87. Sketch
Somewhat popular recently
Easy

88. Sketch
Somewhat popular recently
Easy
Flat pricing ($50/once)

89. Sketch
Somewhat popular recently
Easy
Flat pricing ($50/once)
Some scripting!

90. Sketch
Somewhat popular recently
Easy
Flat pricing ($50/once)
Some scripting!
Winner for now!

91. Sketchtool for
command line interface

92. Sketchtool for
command line interface
My artwork = 1 sketch file

93. Sketchtool for
command line interface
My artwork = 1 sketch file
https://github.com/wkoszek/sensorama-artwork

97. Rendering is
completely automated
./regen.sh

98. Updating is
completely automated
./update.sh
git commit ../sensorama-ios

99. Let me know how your
flow works like!

100. OSS truth about design
tools

101. OSS truth about design
tools
Imperfect for GitHub work (binary formats)

102. Usability
tests
3

103. Asking people to tell you how
to make stuff work is great

104. Users getting confused:
great feedback for you

105. Users give a lot of "I
don't get it" feedback

106. Users give a lot of
"I don't get it" feedback
Especially for a geeky app like this

107. See my YouTube channel "Building
Real-World iOS App"
https://github.com/wkoszek/sensorama-ios

108. Implementation
4

109. 1st version
Android!

110. Android tools - fine for
smaller OSS projects

111. Bigger projects: you
feel like Java/Gradle
compilers should be
3-5x faster

112. Android tools - fine for
smaller OSS projects
M
ain IDE not
Open-Source

113. Gradle (build system)
= Open Source

114. Android vs iOS
Tools

115. Android vs iOS
Tools
Tie

116. Android vs iOS
Tools
Tie
Too much XML

117. Android vs iOS
Tools
Tie (XCode = Android Studio in problems)
e.g.: Too much XML

118. Android vs iOS
Tools
Tie
Too much XML

119. Open Source
Good and BAD parts
5

120. Good stuff

121. A lot of functionality

122. A lot of functionality
for FREE !

123. Sensorama is using
23OSS modules

124. Too many to
mention them all,
but lets looks at
what I've put into
it quickly

125. Fabric/Crashlytics
Must have for
debugging

126. NSLogger for
convenient
debugging

127. Realm for
data model

128. AWS SDK
for storage

129. Auth0 for
authorization

130. Mailgun for
e-mail
handling

131. BZIP2 for
very good
compression

132. InAppSettings
for the
settings screen

133. All this stuff is
Open Source!!!

134. Just go on GitHub and
search for things you
need

135. I have 2
takes on it

136. Take 1

137. Without OSS
building app like
Sensorama wouldn't
be possible

138. Take 2

139. Using only my
own stuff would
make it more fun

140. Using only my
own stuff would
make it more fun
but would take more time

141. Using only my
own stuff would
make it more fun
but would take more time
or NOT?

142. Take 3

143. Use it
"as expected"
and you'll be fine

144. If you deviate from
normal use case, you're
completely alone

145. Cool thing

146. Basically $0 for
code development

147. Many companies
offer tools for FREE
to Open-Source
projects

148. e.g.: Auth0 has a nice,
fully-featured version of
their product available
to Open-Source projects

149. You project is OSS?
No need to pay for GitHub or Travis-CI

150. JetBrains gave me
their tools to try out
for free too

151. Some lessons
learned

152. OSS modules:
CocoaPods

153. Repository for all
cool iOS stuff

155. CocoaPods is great!

156. CocoaPods is great!
Sort of

157. CocoaPods is great!
Sort of
Takes your XCode project and modifies it

158. CocoaPods is great!
Sort of
Takes your XCode project and modifies it
in ... unreadable ways (XML)

159. CocoaPods is great!

160. Conclussion 1

161. Conclusion 1
You need to know how to use it well

162. CocoaPods is Ruby

163. CocoaPods is Ruby
Podfile is like Gemfile

164. CocoaPods is Ruby
Podfile is like Gemfile
Use specific version of the modules

165. CocoaPods is Ruby
Podfile is like Gemfile
Use specific version of the modules
Will help you stay out of trouble

166. CocoaPods is adding
more complexity

167. CocoaPods is adding
more complexity
and dependency on network, GitHub and other people
repositories

168. CocoaPods is adding
more complexity
and dependency on network, GitHub and other people
repositories

169. CocoaPods is adding
more complexity
and dependency on network, GitHub and other people
repositories
Matters if you work over the tethered connection

170. Conclusion 2

171. Conclusion 2
Commit files from Cocoa

172. Conclusion 2
Commit files from Cocoa
At least you'll be able to see what changes

173. Might be tons of MBs of code, but at
least you can "git diff" it

174. Some modules are
hundreds of lines of code

175. Conclusion 3
My next project will use Carthage

176. Carthage

177. Carthage
Building you frameworks which you
later integrate

178. Conclusion 4

179. Most stuff just works

180. Most stuff sometimes works

181. 1st Android version was using
Parse SDK

182. 1st Android version was using
Parse SDK
Shut down

183. Travis-CI

184. Travis-CI
Great and free continuous integration
solution!

185. Travis-CI
Great and free continuous integration
solution!
Stuff changes fairly often

186. Travis-CI
Great and free continuous integration
solution!
Slow
and sometimes out of date

187. Other stuff needs monitoring

188. Other stuff needs monitoring
3rd parties you depend on become your
"failure chain"

189. Be prepared for a lot of documentation
reading
(all following images have been made by other great people who put it on imgur.com)

190. Conclusion 5

191. Update stuff only when necessary

192. Updates are when the most breakages
happened

193. Easy to get help from companies

194. Harder from volunteers/free projects

195. How to communicate?

196. Do due diligence, be
clear and post exact data

198. Remember:
volunteers!

200. Report bugs in code
and documentation

202. Talk to people

205. Help with sample
code

207. Done is better than
perfect

208. Other than that -
business as usual

212. If there is documentation

213. BAD stuff
(all following images have been made by other great people who put it on imgur.com)

216. You must do your homework before
asking

217. But also ask early to understand
if you're doing the right thing

218. A LOT of work

220. Using Fastlane for iOS

221. Single-command build and
deploy to Fabric and AppStore

222. Pain to get to work
(Ruby dependencies breaking)
but GREAT once it works

223. Harder than non-OSS
projects

224. Others are looking, so you want to
get to a certain decent code quality

225. Easy to publish too much
(e.g.: your API keys)

226. Easy to publish too much
(e.g.: your API keys)
Regenerating = painful

227. Prepare to unexpected
breakages

228. Follow your vendors
Example of Apple's 2-
factor authentication

229. Summary
6

230. Star Sensorama on
GitHub
http://www.sensorama.org

231. Q/A

232. Building An
Open-Source iOS App
Wojciech Adam Koszek · http://www.koszek.com · ! wkoszek
Silicon Valley Mobile Developers & Designers, Dec 12th, 2016