Great question! Yes, there are IoT projects that focus mostly or entirely on software development — without requiring you to build or tinker with the physical hardware yourself. Here are some types of IoT projects that are primarily software-focused:

1. IoT Cloud Platform Development

1. Building or enhancing platforms that collect, store, analyze, and visualize IoT device data.
2. Example: Creating a dashboard to monitor thousands of sensor readings in real time.
3. Tools: AWS IoT, Microsoft Azure IoT Hub, Google Cloud IoT Core, MQTT brokers, Node-RED.

2. Firmware and Embedded Software Simulation

1. Developing and testing firmware logic in simulation environments without actual devices.
2. Example: Writing device firmware code and running it in virtual IoT device simulators.
3. Tools: IoT simulators, emulators like QEMU.

3. IoT Data Analytics and Machine Learning

1. Building software to process, analyze, and gain insights from IoT sensor data.
2. Example: Developing predictive maintenance algorithms based on sensor data streams.
3. Tools: Python, TensorFlow, Apache Kafka, Spark.

4. IoT Security Software

1. Creating software tools for securing IoT devices and networks (e.g., vulnerability scanners, encryption libraries).
2. Example: Developing intrusion detection systems for IoT networks.
3. Tools: Open-source security frameworks, cryptography libraries.

5. IoT Protocol Development and Middleware

1. Implementing or enhancing communication protocols (MQTT, CoAP, LwM2M) or middleware solutions for device interoperability.
2. Example: Writing software that translates data between different IoT protocols.
3. Tools: Protocol libraries, Node.js, Python.

6. IoT Mobile or Web App Development

1. Developing apps that communicate with IoT devices or cloud services to control or monitor them.
2. Example: A mobile app to remotely control smart home devices.
3. Tools: React Native, Flutter, Angular, REST APIs, WebSockets.

Why software-only IoT projects exist:

1. Hardware prototyping can be expensive or time-consuming.
2. Many IoT systems rely heavily on cloud infrastructure, APIs, and software logic.
3. Simulators and virtual environments allow developers to test without physical devices.
4. Some companies provide "IoT as a Service" where the hardware is managed, and the developer only works on software.