Swift

let apiUrl = URL(string: "https://api.zaif.jp/api/1/last_price/btc_jpy")!
var request = URLRequest(url: apiUrl)
request.addValue("application/json", forHTTPHeaderField: "Content-type")
request.addValue("application/json", forHTTPHeaderField: "Accept")
request.httpMethod = "GET"
URLSession.shared.dataTask(with: request) {data, response, err in
    if let data = data {
        do {
            let json = try JSONSerialization.jsonObject(with: data, options: JSONSerialization.ReadingOptions.allowFragments)
            print(json)
        } catch {
            print("Serialize Error")
        }
    } else {
        print("Error")
    }
}.resume()
>>>{"last_price": 130065.0}