As an AI language model I do not have personal opinions or preferences. However, based on popularity and features, the following are popular real estate platforms or apps for exploring investment opportunities in sustainable industrial properties:

1. LoopNet – a commercial real estate listing site that offers a wide range of industrial properties for sale and lease.

2. Cushman & Wakefield – a global real estate firm that provides a range of investment and leasing services for industrial properties.

3. BiggerPockets – a platform for real estate investors that includes a marketplace for buying and selling properties, including industrial.

4. Realtor.com – a comprehensive listing site that includes industrial properties across the US.

5. CommercialEdge – a commercial real estate data platform that offers market insights and listings for industrial properties.

6. CoStar – a comprehensive commercial real estate database that includes industrial properties.

7. Crexi – a commercial real estate marketplace that includes a range of industrial properties.

8. Buildout – a platform that focuses on marketing commercial real estate properties, including industrial.

9. RealNex – a comprehensive commercial real estate platform that includes industrial properties.

10. Reonomy – a data and analytics platform for commercial real estate that includes industrial properties.