diff --git a/services/identity/src/database.rs b/services/identity/src/database.rs
--- a/services/identity/src/database.rs
+++ b/services/identity/src/database.rs
@@ -58,7 +58,9 @@
 mod one_time_keys;
 mod token;
 mod workflows;
-pub use device_list::{DeviceListRow, DeviceListUpdate, DeviceRow};
+pub use device_list::{
+  DeviceListRow, DeviceListUpdate, DeviceRow, PlatformDetails,
+};
 
 use self::device_list::Prekey;
 
diff --git a/services/identity/src/database/device_list.rs b/services/identity/src/database/device_list.rs
--- a/services/identity/src/database/device_list.rs
+++ b/services/identity/src/database/device_list.rs
@@ -901,6 +901,40 @@
     Ok(())
   }
 
+  #[tracing::instrument(skip_all)]
+  pub async fn update_device_platform_details(
+    &self,
+    user_id: impl Into<String>,
+    device_id: impl Into<String>,
+    platform_details: PlatformDetails,
+  ) -> Result<(), Error> {
+    self
+      .client
+      .update_item()
+      .table_name(devices_table::NAME)
+      .key(ATTR_USER_ID, AttributeValue::S(user_id.into()))
+      .key(ATTR_ITEM_ID, DeviceIDAttribute(device_id.into()).into())
+      .condition_expression(
+        "attribute_exists(#user_id) AND attribute_exists(#item_id)",
+      )
+      .update_expression("SET #platform_details = :platform_details")
+      .expression_attribute_names("#user_id", ATTR_USER_ID)
+      .expression_attribute_names("#item_id", ATTR_ITEM_ID)
+      .expression_attribute_names("#platform_details", ATTR_PLATFORM_DETAILS)
+      .expression_attribute_values(":platform_details", platform_details.into())
+      .send()
+      .await
+      .map_err(|e| {
+        error!(
+          errorType = error_types::DEVICE_LIST_DB_LOG,
+          "Failed to update device platform details: {:?}", e
+        );
+        Error::AwsSdk(e.into())
+      })?;
+
+    Ok(())
+  }
+
   #[tracing::instrument(skip_all)]
   pub async fn get_current_device_list(
     &self,
diff --git a/services/identity/src/grpc_services/authenticated.rs b/services/identity/src/grpc_services/authenticated.rs
--- a/services/identity/src/grpc_services/authenticated.rs
+++ b/services/identity/src/grpc_services/authenticated.rs
@@ -1,13 +1,13 @@
 use std::collections::HashMap;
 
 use crate::config::CONFIG;
-use crate::database::DeviceListUpdate;
+use crate::database::{DeviceListUpdate, PlatformDetails};
 use crate::device_list::SignedDeviceList;
 use crate::{
   client_service::{handle_db_error, UpdateState, WorkflowInProgress},
   constants::{error_types, request_metadata},
   database::DatabaseClient,
-  grpc_services::shared::get_value,
+  grpc_services::shared::{get_platform_metadata, get_value},
 };
 use chrono::DateTime;
 use comm_opaque2::grpc::protocol_error_to_grpc_status;
@@ -699,6 +699,25 @@
     };
     return Ok(Response::new(response));
   }
+
+  #[tracing::instrument(skip_all)]
+  async fn sync_platform_details(
+    &self,
+    request: tonic::Request<Empty>,
+  ) -> Result<Response<Empty>, tonic::Status> {
+    let (user_id, device_id) = get_user_and_device_id(&request)?;
+    let platform_metadata = get_platform_metadata(&request)?;
+    let platform_details = PlatformDetails::new(platform_metadata, None)
+      .map_err(|_| Status::invalid_argument("Invalid platform metadata"))?;
+
+    self
+      .db_client
+      .update_device_platform_details(user_id, device_id, platform_details)
+      .await
+      .map_err(handle_db_error)?;
+
+    Ok(Response::new(Empty {}))
+  }
 }
 
 #[allow(dead_code)]
diff --git a/shared/protos/identity_auth.proto b/shared/protos/identity_auth.proto
--- a/shared/protos/identity_auth.proto
+++ b/shared/protos/identity_auth.proto
@@ -84,6 +84,10 @@
   /* Miscellaneous actions */
 
   rpc FindUserIdentities(UserIdentitiesRequest) returns (UserIdentitiesResponse) {}
+
+  // Updates current device PlatformDetails stored on Identity Service.
+  // It doesn't require any input - all values are passed via request metadata.
+  rpc SyncPlatformDetails(identity.unauth.Empty) returns (identity.unauth.Empty) {}
 }
 
 // Helper types
diff --git a/web/protobufs/identity-auth-client.cjs b/web/protobufs/identity-auth-client.cjs
--- a/web/protobufs/identity-auth-client.cjs
+++ b/web/protobufs/identity-auth-client.cjs
@@ -1176,5 +1176,66 @@
 };
 
 
+/**
+ * @const
+ * @type {!grpc.web.MethodDescriptor<
+ *   !proto.identity.unauth.Empty,
+ *   !proto.identity.unauth.Empty>}
+ */
+const methodDescriptor_IdentityClientService_SyncPlatformDetails = new grpc.web.MethodDescriptor(
+  '/identity.auth.IdentityClientService/SyncPlatformDetails',
+  grpc.web.MethodType.UNARY,
+  identity_unauth_pb.Empty,
+  identity_unauth_pb.Empty,
+  /**
+   * @param {!proto.identity.unauth.Empty} request
+   * @return {!Uint8Array}
+   */
+  function(request) {
+    return request.serializeBinary();
+  },
+  identity_unauth_pb.Empty.deserializeBinary
+);
+
+
+/**
+ * @param {!proto.identity.unauth.Empty} request The
+ *     request proto
+ * @param {?Object<string, string>} metadata User defined
+ *     call metadata
+ * @param {function(?grpc.web.RpcError, ?proto.identity.unauth.Empty)}
+ *     callback The callback function(error, response)
+ * @return {!grpc.web.ClientReadableStream<!proto.identity.unauth.Empty>|undefined}
+ *     The XHR Node Readable Stream
+ */
+proto.identity.auth.IdentityClientServiceClient.prototype.syncPlatformDetails =
+    function(request, metadata, callback) {
+  return this.client_.rpcCall(this.hostname_ +
+      '/identity.auth.IdentityClientService/SyncPlatformDetails',
+      request,
+      metadata || {},
+      methodDescriptor_IdentityClientService_SyncPlatformDetails,
+      callback);
+};
+
+
+/**
+ * @param {!proto.identity.unauth.Empty} request The
+ *     request proto
+ * @param {?Object<string, string>=} metadata User defined
+ *     call metadata
+ * @return {!Promise<!proto.identity.unauth.Empty>}
+ *     Promise that resolves to the response
+ */
+proto.identity.auth.IdentityClientServicePromiseClient.prototype.syncPlatformDetails =
+    function(request, metadata) {
+  return this.client_.unaryCall(this.hostname_ +
+      '/identity.auth.IdentityClientService/SyncPlatformDetails',
+      request,
+      metadata || {},
+      methodDescriptor_IdentityClientService_SyncPlatformDetails);
+};
+
+
 module.exports = proto.identity.auth;
 
diff --git a/web/protobufs/identity-auth-client.cjs.flow b/web/protobufs/identity-auth-client.cjs.flow
--- a/web/protobufs/identity-auth-client.cjs.flow
+++ b/web/protobufs/identity-auth-client.cjs.flow
@@ -136,6 +136,13 @@
     callback: (err: grpcWeb.RpcError,
                response: identityAuthStructs.UserIdentitiesResponse) => void
   ): grpcWeb.ClientReadableStream<identityAuthStructs.UserIdentitiesResponse>;
+
+  syncPlatformDetails(
+    request: identityStructs.Empty,
+    metadata: grpcWeb.Metadata | void,
+    callback: (err: grpcWeb.RpcError,
+               response: identityStructs.Empty) => void
+  ): grpcWeb.ClientReadableStream<identityStructs.Empty>;
 }
 
 declare export class IdentityClientServicePromiseClient {
@@ -232,5 +239,11 @@
     request: identityAuthStructs.UserIdentitiesRequest,
     metadata?: grpcWeb.Metadata
   ): Promise<identityAuthStructs.UserIdentitiesResponse>;
+
+  syncPlatformDetails(
+    request: identityStructs.Empty,
+    metadata?: grpcWeb.Metadata
+  ): Promise<identityStructs.Empty>;
+
 }