| 1 | Communication type | Whether the system works directly between units, through a home Wi-Fi network, or through a mobile app. | For simple room-to-room calling, compare systems that can communicate locally. For remote alerts, check whether an internet connection or account is required. | App-connected features can add flexibility, but may depend on the router, internet service, or a cloud service. |
| 2 | Privacy and security | Encryption details, account requirements, audio storage, microphone controls, and the privacy policy for connected services. | Ask whether communication is encrypted and whether audio is stored or transmitted outside the home. Security features vary by model, so verify them in the product documentation. | Local systems may reduce reliance on cloud services; connected features can require sharing account or device data. |
| 3 | Power and backup | Whether each unit uses mains power, rechargeable batteries, replaceable batteries, or a combination. | Check battery runtime, charging time, low-battery warnings, and whether a unit can be used while charging. Consider backup power if communication is important during an outage. | Battery-powered units are easier to move, while mains-powered units avoid routine recharging but need a nearby outlet. |
| 4 | Range and coverage | Coverage through the actual rooms, floors, and walls where the units will be used. | Test the system in the home before relying on it. Advertised range is often measured under open conditions; walls, floors, and interference can reduce real-world coverage. | A longer stated range does not guarantee reliable communication in every building layout. |
| 5 | Durability and placement | Build quality, charging-port protection, and any published water- or dust-resistance rating. | Choose sturdy units suited to their location. If a unit may be exposed to splashes, check its specific IP rating; water resistance does not automatically mean impact resistance. | More rugged designs may cost more or be heavier. Avoid placing equipment where cords could create a trip hazard. |
| 6 | Ease of use and accessibility | Button size, labeling, volume control, two-way audio, call indicators, and ease of answering or ending a call. | Try the controls with the intended user. Large, clearly labeled buttons and adjustable volume can make everyday operation easier for people with reduced vision or dexterity. | Extra functions can add complexity. Prioritize controls the user can operate independently and reliably. |
| 7 | Total cost | Upfront price plus any extra units, replacement batteries, subscriptions, accessories, or ongoing service fees. | Compare the complete setup needed for the home, not just the price of one unit. Confirm return terms and warranty coverage before purchasing. | A lower purchase price may not include all required units or connected services; ongoing fees can increase the long-term cost. |