Slides of my presentation at the NIER track of the 41th International Conference on Software Engineering (ICSE 2019). The paper is available here: http://www.ivanomalavolta.com/files/papers/ICSE_2019_NAPPA.pdf

1. Navigation-aware and Personalized
Prefetching of Network Requests in
Android Apps
Ivano Malavolta, Vrije Universiteit Amsterdam
Francesco Nocera, Polytechnic University of Bari
Patricia Lago, Vrije Universiteit Amsterdam
Marina Mongiello, Polytechnic University of Bari

2. Network prefetching
2
▣ Most apps interact with backend services
via HTTP-based RESTful interactions
▣ à ~800 ms of latency before showing the
actual data for each request
▣ PREFETCHING = loading data before it is
required to decrease the user-perceived
waiting time
Backend

3. https://api.sn.com/media/ □ / □
https://api.sn.com/media/ □ / □
https://api.sn.com/group/ □
https://api.sn.com/ □ /info
https://api.sn.com/ □ /info
https://api.sn.com/ /friends
Intuition
3
Home
Profile
Friends
24
ivanouId
Extras
Group
Page
Media
3
10 15
Backend
AdditionalInfo
5
2
ivano
▣ Extended Navigation Graph
(ENG)
userId
intent
intent
intent
intent
intent
intent

4. NAPPA
4
Navigation-
Aware
Personalized
Prefetching of
Android apps
Main characteristics
□ Android activities as black boxes
■ Lightweight
■ High level of abstraction
□ Prefetching algorithm-independent
□ Adapts to each user navigation patterns
□ The ENG is built at run-time
■ Reflection
■ Multi-threading
■ ...
https://api.sn.com/media/ □ / □
https://api.sn.com/media/ □ / □
https://api.sn.com/group/ □
https://api.sn.com/ □ /info
https://api.sn.com/ □ /info
https://api.sn.com/ /friends
Home
Profile
Friends
24
au53defguId
Extras
Group
Page
Media
3
10 15
Backend
AdditionalInfo
5
2
uId

5. NAPPA at development time
5
Original
app
Extract
activities
Inject navigation
probes
Inject extra
probes
ENG
instrumentation
Instantiate
network
interceptor

6. NAPPA at run-time
6
Prefetching-enabled app
Instrumented
code
Extras
monitor
Prefetcher
Backend
Network
interceptor
0.8
0.10.1
0.5
0.5
URL map
ENG
triggers
populates
fetches
fetches
analyses
Navigation
monitor
fetches
update

7. What’s next?
7
▣ Empirical evaluation
▣ Different prefetching algorithms
□ Greedy algorithm à ENG as a Markov chain?
▣ Detecting dynamic URL fragments beyond intent extras
□ URL fragments emerging from user input, local DBs, shared preferences,
etc.
□ Dynamic taint analysis?
▣ Extend the current prototype
□ https://github.com/S2-group/NAPPA
DATASET OF REAL
USAGE SCENARIOS
NEEDED!