MultiSIM — One Number, Every Device
MultiSIM (also called NumberShare or multi-device SIM) allows a single phone number and data plan to be shared across multiple devices — enabling employees to take calls and messages on their tablet, smartwatch, or laptop using the same number as their primary phone, without managing separate plans for each device.
What RLM Delivers on MultiSIM Strategy
Executives and mobile professionals increasingly work across multiple devices — answering calls on a tablet in a meeting room, checking messages on a smartwatch during a commute, and using a laptop cellular connection when traveling. MultiSIM eliminates the friction of managing separate devices and numbers, creating a seamless multi-device experience from a single carrier plan. RLM advises on MultiSIM strategy and carrier program evaluation.
How We Approach MultiSIM Strategy
How we run a MultiSIM Strategy engagement: establish the baseline, evaluate the market on evidence, negotiate, then stay through deployment.
Multi-Device Workflow Assessment
We document the multi-device use cases across your organization — identifying the employee roles that would benefit from MultiSIM, the device combinations in use, and the communication workflow gaps that MultiSIM addresses.
Carrier Program Evaluation
We evaluate MultiSIM programs across AT&T NumberSync, Verizon NumberShare, and T-Mobile DIGITS — comparing included device limits, monthly fees per additional device, and the device compatibility that determines program viability.
MDM & Security Design
We design the MDM approach for MultiSIM deployments — ensuring secondary devices are enrolled and managed equivalently to primary devices, with appropriate security policies and the remote wipe capability for lost secondary devices.
Cost-Benefit Analysis
We model the cost of MultiSIM programs against the productivity value of multi-device connectivity — comparing carrier program fees against the alternative of separate plans for each device type.
MultiSIM Strategy Evaluation Criteria
How we run a MultiSIM Strategy engagement: establish the baseline, evaluate the market on evidence, negotiate, then stay through deployment.
Carrier Program Fee Structure
MultiSIM programs charge per additional device per month. Evaluate the fee structure against actual multi-device adoption — programs that sound compelling can become expensive when adopted broadly.
Smartwatch Calling Reliability
Smartwatch calling over MultiSIM works well for short interactions but has limitations for extended calls. Evaluate the use case fit before standardizing smartwatch calling as a primary communication channel.
International Availability
MultiSIM functionality often doesn't extend to international roaming — the secondary devices may not be reachable when traveling. Evaluate international limitations for mobile employee use cases.
App Synchronization
MultiSIM handles calls and SMS, but business messaging apps (Teams, Slack) may not synchronize notifications across devices without separate configuration. Evaluate the full communication experience across all intended devices.
Security on Secondary Devices
Secondary devices may have weaker physical security than primary phones — tablets left in conference rooms, smartwatches accessible without PIN. Evaluate the security posture of secondary devices before enabling access to business communications.
"RLM helped us rationalize our mobile fleet across four carriers and cut our monthly spend by 31%. They handled the whole transition — we didn't lose a single device."
The benchmark comes first. Without a baseline, “savings” is just a number a vendor gave you.
Where This Matters Most
Sector-specific considerations we see repeatedly in mobility engagements.
A Sample of the Mobility Providers We Evaluate
RLM is vendor neutral. These are among 600+ providers in our evaluation set — inclusion here is not an endorsement, and we are paid by the provider you choose, not by any provider in particular. How that works →
Thinking About MultiSIM Strategy?
Talk to an RLM advisor who specializes in enterprise mobility. Vendor-neutral guidance from assessment through deployment.