Until now it was not my Main Idea for this Board but in fact Datalogging is also a nice choice ;-)

I created a simple programm to read data from A0 and send it cyclically by Serial.

The intent of the Parameters is to calibrate the readout using some voltage reference values.

Simply note them in Excel and then calculate the correction equation.

The "GUI" is a weng German this time ;-)

Please find some code below :-)

/*
  Analog input, analog output, serial output
 
 Reads an analog input pin, maps the result to a virtual float Value
 and uses the result to calculate a Voltage Value and prints the results to the serial monitor.
 
 The circuit:
 * Connect some voltage potential to A0
 * Connect Ground to a common ground
 * Connect status LEDs on D3 (RED), 5(Blue), 6 (Green)
 * Optional: Connect RX/TX via BlueTooth
 
 created 29 Dec. 2008
 modified 9 Apr 2012 by Tom Igoe
 Extended 30.11.2016 by Stefan-Xp
 
 This example code is in the public domain.
  */

// These constants won't change.  They're used to give names
// to the pins used:
const int analogInPin = A0;  // Analog input pin that the potentiometer is attached to
const int analogOutPin = 9; // Analog output pin that the LED is attached to

int sensorValue = 0;        // value read from the pot
int outputValue = 0;        // value output to the PWM (analog out)

// Variable parameters
int factor = 1; 
int offset = 0;
int delayS = 2;

// Ids for variable parameters
#define FACTOR 1
#define OFFSET 2
#define DELAY 3

int delayCount = 0; // Count for the Delay (Steps of 100ms)
byte inByte = 0;    // Input byte by Serial Port

void setup() {
  // initialize serial communications at 9600 bps:
  Serial.begin(9600); 
  
  // Define some Outputs
  pinMode(3, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  
  digitalWrite(5, HIGH);
}

// This sub writes the Raw and the calculated Value on the Serial
void printVoltage()
{
  int VoltageValue = 0;
  
  digitalWrite(5, LOW);
  digitalWrite(6, HIGH);
  
  sensorValue = analogRead(analogInPin);            
  // map it to the range of the analog out:
  outputValue = map(sensorValue, 0, 1023, 0, 5000);  
  VoltageValue = (outputValue*factor + offset);
  // change the analog out value:
  //analogWrite(analogOutPin, outputValue);           

  // print the results to the serial monitor:
  Serial.print("RAW = " );                       
  Serial.print(outputValue);
  Serial.print("\t Voltage = ");     
  Serial.print(VoltageValue/1000,DEC);   
  Serial.print(","); 
  if(abs(int(VoltageValue)%1000) < 100)
    Serial.print("0"); 
  if(abs(int(VoltageValue)%1000) < 10)
    Serial.print("0"); 
  Serial.print(abs(int(VoltageValue)%1000),DEC);   
  Serial.println("V");   
  
  
  delay(10);
  digitalWrite(5, HIGH);
  digitalWrite(6, LOW);
  return;
}
 
// This sub checks if there are Numbers entered by the Console. 
void checkForNewNumberInput ()
{  
   while(1)  
   {
       if(Serial.available() > 0)
       {
         inByte = Serial.read();
         
         if(inByte >= '0' && inByte <= '9')
         {
           break;
         }
         else
         {
           Serial.print("Err : ");
           Serial.print(inByte);  
           Serial.print(" ");  
           Serial.println((char)inByte);  
         }
       } 
     
   }
}

// This sub sets a parameter with 4 bytes of numbers from Serial
void setParameter(byte Parameter)
{
  float Value = 0;
  
  digitalWrite(3, HIGH);
  digitalWrite(6, LOW);
  
  Serial.print(" eingeben: ");
  
  checkForNewNumberInput();
  Value = (inByte-'0')*1000;
  checkForNewNumberInput();
  Value = (Value + (inByte-'0')*100);
  checkForNewNumberInput();
  Value = (Value + (inByte-'0')*10);
  checkForNewNumberInput();
  Value = (Value + (inByte-'0'));
  
  switch(Parameter)
  {
     case FACTOR: Serial.print("Factor = "); factor = Value/1000; break;   
     case OFFSET: Serial.print("Offset = "); offset = Value; break;   
     case DELAY:  Serial.print("Delay = "); delayS = Value; break; 
  }
  
  Serial.println(Value);
  digitalWrite(3, LOW);
  digitalWrite(6, HIGH);
}

// The usual thing..
void loop() {
  // read the analog in value:
  if(delayCount >= delayS*10)
  {
    printVoltage();
    delayCount = 0;
  }
  delayCount++;

  // if there is new Data on the Serial... 
  if (Serial.available() > 0)
  {
    // get incoming byte:
    inByte = Serial.read();
    Serial.print("Bitte ");
    switch(inByte)
    {
      case 'f': Serial.print("Factor [1.000]"); 
                setParameter(FACTOR);
                break;
                
      case 'o': Serial.print("Offset [10.00]");
                setParameter(OFFSET);
                break;
                
      case 't': Serial.print("Zeitabstand [s]:"); 
                setParameter(DELAY);
                break;
                
      case 'i':           
      case '?': Serial.println();
                Serial.println("*** AnalogDataLogger V1.0"); 
                Serial.println("*** 2016-11-30 Stefan-Xp"); 
                Serial.println("* f = Factor in Tausendstel 1x = 1000");
                Serial.println("* o = Offset in Hundertstel +1 = 0100");
                Serial.println("* t = Time in Sekunden 10s     = 0010");
                Serial.println("* i = Info"); 
                Serial.println("** Aktuelle Parameter:");
                Serial.print("* f = Factor = ");
                Serial.println(factor);
                Serial.print("* o = Offset = ");
                Serial.println(offset);
                Serial.print("* t = Time   = ");
                Serial.println(delayS);  
                //Let it stay at least 5s              
                delay(5000);
                break;
                i
      default:  Serial.println(" gueltigen Key eingeben!");    
    }
  }
  
  // wait 100 milliseconds before the next loop
  // for the analog-to-digital converter to settle
  // after the last reading:
  delay(100);                     
}

Still nothing for the 1k Challenge ;)