When evaluating smart calculators, prioritize dual-power systems (solar and battery) to ensure long-term reliability. For advanced models, check the display resolution (LCD or LED) and whether it supports multi-line display for complex equations. If the device includes 'smart' features like Bluetooth connectivity or app synchronization, verify the chipset stability and internal memory capacity. Additionally, ensure the button lifespan is rated for at least 500,000 presses to meet commercial durability standards.