*This article is part of a recurring series in which we open, test, and dissect AI apps and services making waves in South Korea. The seventh instalment examines A. (pronounced "A-dot"), the AI agent app from SK Telecom, South Korea's largest mobile carrier.*

Background

A. was first unveiled by SK Telecom in May 2022 and officially launched on 26th September 2023. In its early form it was little more than a conversational AI chatbot. In October 2024, however, the company folded its existing T-Phone app into a rebranded "A. Phone", adding call recording and summarisation features. In June 2025 it introduced "Note" — a voice transcription and summarisation tool — along with "Briefing", a beta feature that organises the user's schedule and relevant information. An August 2025 update, version 4.0, introduced agentic workflows, allowing the AI to carry out multi-step tasks autonomously.

SK Telecom reported monthly active users (MAU) of more than ten million as of September last year. Of those, roughly 4.5 million accessed A. directly through its app or website, while a further 5.5 million used A.-powered features embedded within other SK Telecom services such as its phone app, B tv (its IPTV platform), and Tmap (its navigation service).

Core features

The service's central proposition is organising what users say and hear. Its call-summary function transcribes conversations and condenses them into key points; at launch, usage was capped at 30 summaries per month. The Note feature transcribes and summarises recordings of meetings or lectures; a March update added diagram generation, folder organisation, in-app editing, and selective sharing. A home-screen widget for calendar events was also introduced, and conversation memory can now be toggled on or off by the user.

The most significant recent addition came in a 30th June update. A new function called "Agent Call" takes over the tedious preamble of calling a customer-service centre or restaurant: when a user dials a business registered in A.'s directory, the AI manages the call autonomously until a human agent answers. It displays real-time subtitles and an interactive voice-response (IVR) navigation screen, and holds the line if the wait is prolonged. A separate "AI Messages" feature scans reservation confirmations and promotional texts, extracting schedules, locations, expiry dates, and voucher codes — all processed on-device using Google's LiteRT on-device AI framework, which avoids sending the data to external servers. The update also added automatic task generation: the app analyses calls and messages to populate a to-do list with suggested follow-up actions. These on-device features are restricted to Samsung Galaxy S24 or newer handsets (with at least 8GB of RAM) and iPhones 15 Pro or newer running iOS 26.

Strengths and limitations

A.'s principal strength is that it weaves AI assistance into the everyday routines of calling and texting, without requiring users to open a separate application. Agent Call — the idea of letting an AI endure hold music on the user's behalf — is the kind of visceral convenience that users can appreciate immediately. Expanding on-device processing also addresses legitimate privacy concerns by reducing the volume of personal data transmitted to the cloud.

Yet several weaknesses are apparent. The reported user figures are contested: while SK Telecom cites ten million MAU, industry observers note that downloads and active usage of the standalone app appear to remain in the low millions. Privacy concerns have also attracted regulatory scrutiny. During parliamentary hearings (South Korea's equivalent of select committee appearances), a lawmaker from the main opposition Democratic Party pointed out that A. collects not only call transcripts but also text, voice, images, and documents entered by users; that this data is retained for two years; and that it is not deleted immediately upon account closure.

Service reliability is another challenge. On 6th August the platform suffered an outage attributed to an error in its large language model.

Perhaps most pressing is monetisation. SK Telecom went so far as to amend its terms of service in preparation for charging for the Note feature, then quietly shelved the plan. At the MWC technology conference in March, the company's chief technology officer explained: "There is no point asking people to pay when the service is not yet good enough." For now, A. is effectively free.

Verdict

Whereas Clova Note — reviewed in an earlier instalment of this series — is an app for organising recorded content, A. aims to scatter AI assistance across calls, messages, and calendars, positioning itself as a virtual assistant that handles the mundane business of daily life on the user's behalf. The Agent Call concept points in a convincing direction. But device restrictions, privacy concerns, opaque user metrics, and an unresolved revenue model mean the service is best characterised, for now, as a capable free AI assistant that has yet to justify a price tag.

★★★☆☆ (3.0/5.0)

In one line "An AI willing to wait on hold for you — but the value of the service itself is still on hold."