# Initial call (30 min) with Marcel R. G. Berger

> Your app runs. I take care of the rest. This call is for companies without their own tech team: your developer is gone, an AI prototype has to go live, the store rejected your app, a customer is reviewing you as a supplier, or you are planning a new app. How the call works: • Tell me what happened. Plain words, no tech knowledge needed. • Together we work out the next step: usually an App Check, sometimes a takeover, a rescue or a new build straight away, with a rough budget and timeline. • You leave with a clear written next step. No prep, no pitch, no obligation. Teams with their own IT are welcome too; for several systems or an investment decision the next step is usually an Architecture Review. You talk to Marcel directly, the architect who will be accountable for your app. Fixed prices for every step: theapparchitect.com/pricing — The App Architect is a brand of DigitalFreedom Global LLC. Imprint · Privacy

- Host: Marcel R. G. Berger
- Duration: 30 min
- Location: MS Teams
- Host time zone: Europe/Berlin
- Confirmation: Bookings are confirmed instantly.
- Booking page: https://cal.com/marcelrgberger/consultation
- Event type id: 4335893

## Check availability

```http
GET https://api.cal.com/v2/slots?eventTypeId=4335893&start=YYYY-MM-DD&end=YYYY-MM-DD&timeZone=<IANA time zone>
cal-api-version: 2024-09-04
```

The response is `{"data":{"YYYY-MM-DD":[{"start":"<ISO 8601 with offset>"}]}}`; no API key is needed.

## Book

```http
POST https://api.cal.com/v2/bookings
cal-api-version: 2026-02-25
Content-Type: application/json

{
  "eventTypeId": 4335893,
  "start": "<UTC ISO 8601 start from the slots response>",
  "attendee": {
    "name": "…",
    "email": "…",
    "timeZone": "<IANA time zone>"
  },
  "guests": [
    "guest@example.com"
  ],
  "bookingFieldsResponses": {
    "topic": "…",
    "company": "…",
    "notes": "…"
  }
}
```

- Required fields: `name` (Your name), `email` (Email address)
- Optional fields: `topic` (What is it about?), `company` (Company), `notes` (Anything I should know beforehand?), `guests` (Add guests)
- `name` and `email` go in `attendee` and `guests` is a list of emails; every other field goes in `bookingFieldsResponses` under its name.