|
| 1 | +--- |
| 2 | +title: " On‑Device AI Goes Mainstream on Android" |
| 3 | +description: "On-device AI / Edge AI / Mobiel AI / Local AI - whatever the name; it is already very possible today and has many benefits. Here's how you can get started (now or whenever you're ready)" |
| 4 | +slug: edge-ai-anywhere-anytime |
| 5 | +image: |
| 6 | +--- |
| 7 | + |
| 8 | +import Head from '@docusaurus/Head'; |
| 9 | + |
| 10 | +# On‑Device AI Goes Mainstream on Android |
| 11 | +This article is a written recap of my [Droidcon Berlin 2025 talk](https://www.youtube.com/watch?v=jwOToFCQ41Y), so the focus is on Android and Mobile AI in the hands-on, practical part. You can [find the slides here](#) (slideshare/pdf link). In this talk, we explored why the shift towards Edge AI matters, especially for developers, and how developers can get started and what to . |
| 12 | + |
| 13 | +:::note |
| 14 | +**Note:** Edge AI may also be called **On-device AI**, **Mobile AI**, or **Local AI**. |
| 15 | +::: |
| 16 | + |
| 17 | +Artificial Intelligence (AI) is shifting from the cloud to the **edge** — onto our phones, cars, and billions of connected devices. This move, often described as **Edge AI** ([What is Edge AI?](https://objectbox.io/on-device-vector-databases-and-edge-ai/)), unlocks AI experiences that are private, fast, and sustainable. |
| 18 | + |
| 19 | +--- |
| 20 | + |
| 21 | +## Why Edge AI Now? |
| 22 | + |
| 23 | +Two megatrends are converging: |
| 24 | + |
| 25 | +- **[Edge Computing](https://objectbox.io/dev-how-to/edge-computing-state-2025)** - Processing data where it is created, on the device, locally, at the egd of the network, is called "Edge Computing" and it is growing |
| 26 | +- **AI** - AI capabilities and use are expanding rapidly and without a need for further explanation |
| 27 | +<img src="/static/img/edge-ai/edge-ai.jpg" alt="Edge AI: Where Edge Computing and AI intersect" /> |
| 28 | + |
| 29 | +--> where these two trends overlap (at the intersection), it is called Edge AI (or local AI, on-device AI, or with regards to a subsection: "Mobile AI") |
| 30 | + |
| 31 | +The shift to Edge AI is driven by use cases that: |
| 32 | +* need to work offline |
| 33 | +* have to comply with specific privacy / data requirements |
| 34 | +* want to transfer more data than the bandwidth will allow |
| 35 | +* need to meet realtime or (QoS) specific reponse rate requirements |
| 36 | +* are not economically viable when using the cloud / a cloud AI |
| 37 | +* want to be sustainable |
| 38 | + |
| 39 | +<img src="/static/img/edge-ai/edge-ai-benefits.jpg" alt="Edge AI drivers (benefits)" /> |
| 40 | + |
| 41 | +If you're interested in the sustianability aspect, see also: [Why Edge Computing matters for a sustainable future](https://objectbox.io/why-do-we-need-edge-computing-for-a-sustainable-future/) |
| 42 | + |
| 43 | +## Why it's not Edge AI vs. Cloud AI - the reality is hybrid AI |
| 44 | + |
| 45 | +Of course, while we see a market shift towards Ede Computing, there is no Edge Computiung vs. Cloud Computing - the two complement each other and the question is mainly: How much edge does your use case need? |
| 46 | + |
| 47 | +<img src="/static/img/edge-ai/cloud-to-edge-continuum.jpg" alt="Edge AI drivers (benefits)" /> |
| 48 | + |
| 49 | +Every shift in computing is empowered by core technologies |
| 50 | +<img src="/static/img/edge-ai/computing-shifts-empowered-by-core-tech.jpg" alt="Every shift in computing is empowered by core technologies" /> |
| 51 | + |
| 52 | +## What are the core technologies empowering Edge AI? |
| 53 | + |
| 54 | +If every megashift in computing is powered by core tech, what are the core technologies empowering the shift to Edge AI? |
| 55 | + |
| 56 | +Typically, Mobile AI apps need **three core components**: |
| 57 | +1. An **on-device AI model (e.g. [SLM](https://objectbox.io/the-rise-of-small-language-models/))** |
| 58 | +2. A [**vector database**](https://objectbox.io/vector-database/)) |
| 59 | +3. **Data sync** for hybrid architectures ([Data Sync Alternatives](https://objectbox.io/data-sync-alternatives-offline-vs-online-solutions/)) |
| 60 | + |
| 61 | +<img src="/static/img/edge-ai/core-tech-enabling-edge-ai.jpg" alt="The core technologies empoewring Edge AI" /> |
| 62 | + |
| 63 | + |
| 64 | +## A look at AI models |
| 65 | + |
| 66 | +### The trend to "bigger is better" has been broken - the rise of SLM and Small AI models |
| 67 | + |
| 68 | +Large foundation models (LLMs) remain costly and centralized. In contrast, [**Small Language Models (SLMs)**] bring similar capabilities in a lightweight, resource-efficient way. |
| 69 | + |
| 70 | +<img src="/img/edge-ai/slm-quality-cost.png" alt="SLM quality and cost comparison" /> |
| 71 | +- Up to **100x cheaper** to run |
| 72 | +- Faster, with lower energy consumption |
| 73 | +- Near-Large-Model quality in some cases |
| 74 | + |
| 75 | +This makes them ideal for **local AI** scenarios: assistants, semantic search, or multimodal apps running directly on-device. However.... |
| 76 | + |
| 77 | +### Frontier AI Models are still getting bigger and costs are skyrocketing |
| 78 | +<img src="/img/edge-ai/slm-quality-cost.png" alt="SLM quality and cost comparison" /> |
| 79 | + |
| 80 | +### Why this matters for developers: Monetary and hidden costs of using Cloud AI |
| 81 | + |
| 82 | +Running cloud AI comes at a cost: |
| 83 | + |
| 84 | +- **Monetary Costs**: Cloud cost conundrum ([Andressen Horowitz 2021](https://a16z.com/the-cost-of-cloud-a-trillion-dollar-paradox/)) is fueled by cloud AI; margins shrink as data center and AI bills grow ([Gartner 2025](https://x.com/Gartner_inc/status/1831330671924572333 |
| 85 | +)) |
| 86 | +- **Dependency**: Few tech giants hold all major AI models, the data, and the know-how, and they make the rules (e.g. thin AI layers on top of huge cloud AI models will fade away due to vertical integration) |
| 87 | +- **Data privacy & compliance**: Sending data around adds risk, sharing data too (what are you agreeing to?) |
| 88 | +- **Sustainability**: Large models consume waqy more energy, and transmitting data unnecessarily consumes way more energy too (think of this as shopping apples from New Zealand in Germany) ([Sustainable Future with Edge Computing](https://objectbox.io/why-do-we-need-edge-computing-for-a-sustainable-future/)). |
| 89 | +<img src="/img/edge-ai/slm-quality-cost.png" alt="SLM quality and cost comparison" /> |
| 90 | + |
| 91 | +### What about Open Source AI Models? |
| 92 | + |
| 93 | +Yes, they are an option, but be mindful of potential risks and caveats. Be aware that you also pay to be free of liability risks. |
| 94 | +<img src="/img/edge-ai/slm-quality-cost.png" alt="SLM quality and cost comparison" /> |
| 95 | + |
| 96 | +### While SLM are all the rage, it's really about specialised AI models in Edge AI (at this moment...) |
| 97 | +<img src="/img/edge-ai/slm-quality-cost.png" alt="SLM quality and cost comparison" /> |
| 98 | + |
| 99 | + |
| 100 | +## On-device Vector Databases are the second essential piece of the Edge AI Tech Stack |
| 101 | + |
| 102 | +- Vector databases are basically [the databases for AI applications](https://objectbox.io/empowering-edge-ai-the-critical-role-of-databases/). AI models work with vectors (vector embeddings) and vector databases make working with vector embeddings easy and efficient. |
| 103 | +- Vector databases offer powerful vector search and querying capabilities, provide additional context and filtering mechanisms and give AI applications a longterm memory. |
| 104 | +- For most AI applications you need to use a vector database, e.g. Retrieval Augmented Generation (RAG) or agentic AI, but they are also used to make AI apps more efficient, e.g. reducing LLM calls and providing faster responses. |
| 105 | + |
| 106 | +:::info |
| 107 | +On-device (or Edge) vector databases have a small footprint (a couple of MB, not hundreds of MB) and are optimized for efficiency on resource-restricted devices. |
| 108 | +::: |
| 109 | + |
| 110 | +(Note: Edge Vector databases, or on-device vector databases, are still rare. ObjectBox was the first on-device vector database available on the market. Some server- and cloud-oriented vector databases have recently begun positioning themselves for edge use. However, their relatively large footprint often makes them more suitable for laptops than for truly resource-constrained embedded devices. More importantly, solutions designed by scaling down from larger systems are generally not optimized for restricted environments, resulting in higher computational demands and increased battery consumption.) |
| 111 | + |
| 112 | +<img src="/img/edge-ai/vector-database.png" alt="Vector Databases" /> |
| 113 | + |
| 114 | + |
| 115 | +## Developer Story: On-device AI Screenshot Searcher Example App |
| 116 | + |
| 117 | +To test the waters, I built a [**Screenshot Searcher** app with ObjectBox Vector Database](https://github.com/objectbox/on-device-ai-screenshot-searcher-example): |
| 118 | + |
| 119 | +- OCR text extraction with ML Kit |
| 120 | +- Semantic search with MediaPipe and ObjectBox |
| 121 | +- Image similarity search with TensorFlow Lite and Objectbox |
| 122 | +- Image categorization with ML Kit Image Labeling |
| 123 | + |
| 124 | +This was easy and took less than a day. However, I learned more with the stuff I tried that wasn't easy... ;) |
| 125 | + |
| 126 | +### What I learned about text classification (and hopefully helps you) |
| 127 | +<img src="/img/edge-ai/on-device-text-classification.png" alt="On-device Text Classification Learnings" /> |
| 128 | + |
| 129 | +--> See Finetuning.... without Finetuning, no model, no text classification. |
| 130 | + |
| 131 | +### What I learned about finetuning (and hopefully helps you) |
| 132 | +<img src="/img/edge-ai/finetuning-text-model-learnings.png" alt="Finetuning Learnings (exemplary, based on finetuning DBPedia)" /> |
| 133 | + |
| 134 | +--> Finetuning failed --> I will tray again ;) |
| 135 | + |
| 136 | +### What I learned about integrating an SLM (Google's Gemma) |
| 137 | + |
| 138 | +Integrating Gemma was super straightforward; it worked on-device in less than an hour (just don't try to use the Android emulator (AVD) - it's not recommended to try and run Gemma on the AVD, and it also did not work for me). |
| 139 | +<img src="/img/edge-ai/using-gemma-on-android.png" alt="Using Gemma on Android" /> |
| 140 | + |
| 141 | + |
| 142 | +In this example app, we are using Gemma to enhance the screenshot search with an additional AI layer: |
| 143 | + - Generates intelligent summaries from OCR text |
| 144 | + - Create semantic categories and keywords |
| 145 | + - Enhance search queries with synonyms and related terms |
| 146 | + |
| 147 | + |
| 148 | +## Overall assessment of the practical, hands-on state of On-device AI on Android |
| 149 | + |
| 150 | + |
| 151 | +It's already fairly easy - and vibe coding an Edge AI app very doable. While of course I would recommend the latter only for prototyping and testing, it is amazing what you can do on-device with AI already, even not being a developer! |
| 152 | + |
| 153 | + |
| 154 | + |
| 155 | +<img src="/img/edge-ai/final-tech-stack.png" alt="Final Tech Stack" /> |
| 156 | + |
| 157 | + |
| 158 | + |
| 159 | + |
| 160 | +--- |
| 161 | + |
| 162 | +## Key Questions to Ask Yourself |
| 163 | + |
| 164 | +- How much **edge vs. cloud** do you need? |
| 165 | +- Which tasks benefit from **local inference**? |
| 166 | +- What data **must remain private**? |
| 167 | +- How can you make your app **cost-efficient** long term? |
| 168 | + |
| 169 | +--- |
| 170 | + |
| 171 | +## How to Get Started |
| 172 | + |
| 173 | +- Learn about [Local AI](https://objectbox.io/local-ai-what-it-is-and-why-we-need-it/) |
| 174 | +- Explore [Vector Databases](https://objectbox.io/vector-database/) |
| 175 | +- Prototype with the [On-device AI Screenshot Searcher Example](https://github.com/objectbox/on-device-ai-screenshot-searcher-example) |
| 176 | +- Consider [Data Sync](https://objectbox.io/data-sync-alternatives-offline-vs-online-solutions/) for hybrid apps |
| 177 | +- Read more on [Empowering Edge AI with Databases](https://objectbox.io/empowering-edge-ai-the-critical-role-of-databases/) |
| 178 | + |
| 179 | +--- |
| 180 | + |
| 181 | +## Conclusion |
| 182 | + |
| 183 | +We’re at an inflection point: AI is moving from centralized, cloud-based services to decentralized, personal **on-device AI**. With **SLMs**, **vector databases**, and **data sync**, developers can now build AI apps that are: |
| 184 | + |
| 185 | +- Private |
| 186 | +- Offline-first |
| 187 | +- Cost-efficient |
| 188 | +- Sustainable |
| 189 | + |
| 190 | +The future of AI is not just big — it’s also **small, local, and synced**. |
| 191 | + |
| 192 | +<img src="/img/edge-ai/ai-anytime-anywhere.png" alt="AI Anytime Anywhere Future" /> |
| 193 | + |
| 194 | +--- |
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