DYAMO is a company who strive to empower students to succeed in their studies by setting them up with a mentor that the student can depend on for motivation and help. Furthermore, the students should be able to stay anonymous to the mentors. However, DYAMO does not yet have their own platform to work with. This report will serve as a rundown of how the app, specifically made for DYAMO, was developed. This will later be compared to the initial expectations set out before work on the app started. Finally, there will be some suggestions for what could be further developed in the app for the future. The app serves as a place where an adept (student) can communicate with their mentor by sending texts, files (including images and video) and receive reward-stickers. The responsibility of assigning and managing these conversations lies with the admins and moderators. A school management system is also in place, making it easier to manage and delegate responsibilities within said schools. The app mostly delivered on the final expectations, which exceeded the initial somewhat conservative expectations. The one thing not achieved being that notifications on some devices do not work with the app in the background. / DYAMO stravar efter att mojliggora for studenter att lyckas med sina studier genom att para ihop dem med en mentor som studenten kan lita p_a for motivation och hjalp. Studenten ska dessutom kunna forbli anonym gentemot mentorn, dock har inte DYAMO annu n_agon egen app att utfora detta med. Den har rapporten kommer att agera som en genomg_ang av hur appen, som var speci_kt gjord for DYAMO, blev utvecklad. Detta kommer senare att jamforas med de ursprungliga forvantningarna som sattes innan utvecklingen av appen p_aborjades. Slutligen, kommer det _nnas n_agra forslag p_a vad som skulle kunna vidare jobbas p_a om utvecklingen av appen skulle fortsatta. Appen fungerar s_a att en adept (student) kan kommunicera med en mentor genom att skicka text-meddelanden, _ler (inklusive bilder och videor) och ta emot beloningsklisterm arken. Ansvaret av att tilldela och hantera konversationer faller hos admins och moderatorer. Ett skolhanteringssystem _nns ocks_a p_a plats, for att underlatta hantering och delegering av ansvar inom skolorna. Appen levererade mestadels p_a de slutgiltiga forvantningarna, som i sin tur overskred de ursprungliga n_agot konservativa forvantningarna. Det enda som inte uppfylldes var att noti_kationerna p_a vissa enheter inte fungerar nar appen kors i bakgrunden.

This thesis investigates the automation of forensic analysis in identifying and categorising forensically interestingchanges across dierent versions of chat applications on Android platforms. The focus is primarily on thedierentiation of Android Package Kit (APK) using reverse-engineering techniques to reconstruct the originalsource code and comparing the source code from two dierent versions of the APK. Given the rapid evolutionof chat applications and their frequent updates, it is crucial for forensic investigators to understand thesechanges to maintain the integrity of legal investigations.The research introduces a comprehensive framework leveraging the open-source tools, Ghidra and BinDi, toautomate the decompilation and dierential analysis of APK les. This approach not only makes forensicanalysis less complicated but also ensures that investigators can keep pace with the continuous updates in chatapplications.Tests on the system are conducted on various versions of the Signal chat application. These tests aim todemonstrate the proposed tool in capturing signicant changes between APK versions, such as alterations inlogging mechanisms, database interactions, and the use of encryption and cypher libraries.The results conrm that the integration of Ghidra and BinDi provides a solution for automated forensicanalysis, facilitating the identication of changes and categorisation of methods based on their forensicrelevance. The study shows that the tool can pinpoint modications and structural changes, which are essentialfor forensic investigations.

現今因無線通訊技術的進步，使得人們能方便地利用智慧型裝置透過3G，4G和Wi-Fi等技術彼此溝通聊天。其中，聊天應用是最受智慧型裝置使用者歡迎的應用程式。大部分的聊天應用程式需依賴網路以達到訊息交換的目的。然而網路的頻寬是非常有限的，當使用者處在擁擠的環境中時，他們可能會面臨資源耗盡問題。此外，例如在漫遊的情況下有些使用者並沒有行動網路的存取，導致使用者無法使用聊天應用。 因此我們希望利用無線廣播傳輸的特性，開發一個應用於間歇性網路連接的聊天應用程式。然而，廣播傳輸的散播策略若沒有設計得宜，可能導致廣播風暴的問題，使得整體網路效能低落。我們研究的目標是要如何在間歇性網路增加訊息的傳輸效率。為了達成此目標，在我們的研究中考量了許多技術要求，如：訊息具有截止時間與優先權特性、多聊天室應用、傳輸效率。 我們提出了一種兩階段基於網絡編碼設計的訊息散播方法，實現在機會性社群網路中的訊息散播。網絡編碼階段，提高網路頻寬的傳輸效率，也能增加網路傳輸的可靠性；預熱階段能提升網路編碼訊息被解開的機率。最後，利用政大的真實軌跡紀錄評估我們所設計的訊息傳播方法。結果顯示，我們的方法是有效率且優於氾濫式的路由協議和一般的網絡編碼散播技術。 / Nowadays, the advancement of wireless communication technology has allowed people to use smart phones to communicate with each other more easily via 3G/4G, Wi-Fi, etc. One kind of popular mobile Apps is “chat” App. Most chat Apps rely on the Internet to exchange the messages. However, the bandwidth of network is limited in some circumstances. When users stay in the crowded environment, they will face the resource depletion problem. Besides, some people may not subscribe to any cellular network access, e.g. in roaming scenarios. Therefore, we want to develop a novel mobile Chat APP in intermittently connected networks. We utilize the characteristic of the wireless broadcast transmission. However, it may cause the broadcast storm problem without careful design. How to increase the efficiency of message delivery in such intermittently connected networks is our research goal. To achieve this, technical issues in our research involve message priority, multi-chatroom, deadline and transmission efficiency. We proposed a two-phase network coding design for message dissemination to enable the multi-hop instant messaging in Opportunistic Mobile Social Networks. The network coding phase can increase the bandwidth utility and transmission efficiency. Moreover, it can improve transmission robustness and adaptability. The warm up phase can increase the decoding probability of coded packets. Finally, we evaluated our approach with real trace data from NCCU. The results showed that our approach is effective and superior to the flooding based routing protocol and the pure network coding technique.