# App Builder

- [App Builder Overview](/app-builder/app-builder-overview.md)
- [Build Backend](/app-builder/build-backend.md)
- [Functions](/app-builder/build-backend/functions.md)
- [Functions library](/app-builder/build-backend/functions-library.md)
- [Connectors](/app-builder/build-backend/functions-library/connectors.md)
- [Allen-Bradley](/app-builder/build-backend/functions-library/connectors/allen-bradley.md)
- [Email](/app-builder/build-backend/functions-library/connectors/email.md)
- [File I/O](/app-builder/build-backend/functions-library/connectors/file-i-o.md)
- [GraphQL](/app-builder/build-backend/functions-library/connectors/graphql.md)
- [GPIO Counter](/app-builder/build-backend/functions-library/connectors/gpio-counter.md)
- [Heidenhain DNC](/app-builder/build-backend/functions-library/connectors/heidenhain-dnc.md)
- [Heidenhain OPC UA](/app-builder/build-backend/functions-library/connectors/heidenhain-opc-ua.md)
- [HTTP / REST](/app-builder/build-backend/functions-library/connectors/http-rest.md)
- [Hydra MIP](/app-builder/build-backend/functions-library/connectors/hydra-mip.md)
- [Kuando Busylight](/app-builder/build-backend/functions-library/connectors/kuando-busylight.md)
- [Label Printer](/app-builder/build-backend/functions-library/connectors/label-printer.md)
- [Modbus](/app-builder/build-backend/functions-library/connectors/modbus.md)
- [MQTT Client](/app-builder/build-backend/functions-library/connectors/mqtt-client.md)
- [OPC UA Client](/app-builder/build-backend/functions-library/connectors/opc-ua-client.md): Learn how to connect to an OPC UA server using the Heisenware OPC UA integration.
- [OPC UA Server](/app-builder/build-backend/functions-library/connectors/opc-ua-server.md)
- [Operating System (OS)](/app-builder/build-backend/functions-library/connectors/operating-system-os.md)
- [Raspberry Pi GPIO](/app-builder/build-backend/functions-library/connectors/raspberry-pi-gpio.md)
- [RS-232/485](/app-builder/build-backend/functions-library/connectors/rs-232-485.md)
- [Sap Digital Manufacturing](/app-builder/build-backend/functions-library/connectors/sap-digital-manufacturing.md): Beta Feature
- [Siemens S7](/app-builder/build-backend/functions-library/connectors/siemens-s7.md)
- [Zebra RFID IoT](/app-builder/build-backend/functions-library/connectors/zebra-rfid-iot.md)
- [Storage](/app-builder/build-backend/functions-library/storage.md)
- [Relational Database](/app-builder/build-backend/functions-library/storage/relational-database.md)
- [Timeseries Database](/app-builder/build-backend/functions-library/storage/timeseries-database.md)
- [Data Store](/app-builder/build-backend/functions-library/storage/data-store.md)
- [Circular Buffer](/app-builder/build-backend/functions-library/storage/circular-buffer.md)
- [Utilities](/app-builder/build-backend/functions-library/utilities.md)
- [Barcode Generation](/app-builder/build-backend/functions-library/utilities/barcode-generation.md)
- [Counter](/app-builder/build-backend/functions-library/utilities/counter.md)
- [Cron](/app-builder/build-backend/functions-library/utilities/cron.md)
- [Data Processing](/app-builder/build-backend/functions-library/utilities/data-processing.md)
- [Data Simulation](/app-builder/build-backend/functions-library/utilities/data-simulation.md): This article lists and explains all available simulator functions.
- [Event Simulation](/app-builder/build-backend/functions-library/utilities/event-simulation.md)
- [PDF Processing](/app-builder/build-backend/functions-library/utilities/pdf-processing.md)
- [PDF Templates](/app-builder/build-backend/functions-library/utilities/pdf-templates.md)
- [Stopwatch](/app-builder/build-backend/functions-library/utilities/stopwatch.md)
- [Timer](/app-builder/build-backend/functions-library/utilities/timer.md)
- [Users](/app-builder/build-backend/functions-library/utilities/users.md)
- [Agents](/app-builder/build-backend/functions-library/agents.md): Learn how to create, deploy and use Agents (previously called Edge Connectors).
- [Native Agent](/app-builder/build-backend/functions-library/agents/native-agent.md)
- [Docker Agent](/app-builder/build-backend/functions-library/agents/docker-agent.md)
- [LXC Agent (Insys)](/app-builder/build-backend/functions-library/agents/lxc-agent-insys.md)
- [Extensions](/app-builder/build-backend/functions-library/extensions.md)
- [Industrial Blockchain](/app-builder/build-backend/functions-library/extensions/industrial-blockchain.md)
- [RAG AI](/app-builder/build-backend/functions-library/extensions/rag-ai.md)
- [Knowledge Base](/app-builder/build-backend/functions-library/extensions/rag-ai/knowledge-base.md)
- [Chat With Data](/app-builder/build-backend/functions-library/extensions/rag-ai/chat-with-data.md)
- [Process Simulations](/app-builder/build-backend/functions-library/extensions/process-simulations.md)
- [OGC SensorThings API](/app-builder/build-backend/functions-library/extensions/ogc-sensorthings-api.md)
- [Modifier](/app-builder/build-backend/modifier.md)
- [Filter](/app-builder/build-backend/filter.md)
- [Recorder](/app-builder/build-backend/recorder.md)
- [Error handler](/app-builder/build-backend/error-handler.md)
- [Internal File Server](/app-builder/build-backend/internal-file-server.md)
- [Build Frontend](/app-builder/build-frontend.md)
- [Widgets](/app-builder/build-frontend/widgets.md)
- [Input Widgets](/app-builder/build-frontend/widgets/input-widgets.md)
- [Barcode / QR](/app-builder/build-frontend/widgets/input-widgets/barcode-qr.md)
- [Upload](/app-builder/build-frontend/widgets/input-widgets/upload.md)
- [Form](/app-builder/build-frontend/widgets/input-widgets/form.md)
- [Photo](/app-builder/build-frontend/widgets/input-widgets/photo.md)
- [Signature](/app-builder/build-frontend/widgets/input-widgets/signature.md)
- [Trigger Widgets](/app-builder/build-frontend/widgets/trigger-widgets.md)
- [Button](/app-builder/build-frontend/widgets/trigger-widgets/button.md)
- [Display Widgets](/app-builder/build-frontend/widgets/display-widgets.md)
- [Card](/app-builder/build-frontend/widgets/display-widgets/card.md)
- [Chart](/app-builder/build-frontend/widgets/display-widgets/chart.md)
- [Chat](/app-builder/build-frontend/widgets/display-widgets/chat.md)
- [Circular Gauge](/app-builder/build-frontend/widgets/display-widgets/circular-gauge.md)
- [Data Grid](/app-builder/build-frontend/widgets/display-widgets/data-grid.md)
- [Data List](/app-builder/build-frontend/widgets/display-widgets/data-list.md)
- [Data Tiles](/app-builder/build-frontend/widgets/display-widgets/data-tiles.md)
- [Kanban Board](/app-builder/build-frontend/widgets/display-widgets/kanban-board.md)
- [Linear Gauge](/app-builder/build-frontend/widgets/display-widgets/linear-gauge.md)
- [Map](/app-builder/build-frontend/widgets/display-widgets/map.md)
- [Media View](/app-builder/build-frontend/widgets/display-widgets/media-view.md)
- [Pie Chart](/app-builder/build-frontend/widgets/display-widgets/pie-chart.md)
- [Progress Bar](/app-builder/build-frontend/widgets/display-widgets/progress-bar.md)
- [Sankey](/app-builder/build-frontend/widgets/display-widgets/sankey.md)
- [Sparkline](/app-builder/build-frontend/widgets/display-widgets/sparkline.md)
- [Status Lamp](/app-builder/build-frontend/widgets/display-widgets/status-lamp.md)
- [Toast](/app-builder/build-frontend/widgets/display-widgets/toast.md)
- [Value Box](/app-builder/build-frontend/widgets/display-widgets/value-box.md)
- [Dynamic Group](/app-builder/build-frontend/widgets/dynamic-group.md)
- [Pages & Navigation](/app-builder/build-frontend/pages-and-navigation.md)
- [Text, Icons & Images](/app-builder/build-frontend/text-icons-and-images.md)
- [PDF Template Editor](/app-builder/build-frontend/pdf-template-editor.md)
- [Theme Editor](/app-builder/build-frontend/theme-editor.md)
- [Manage App Lifecycle](/app-builder/manage-app-lifecycle.md)