How it works?

Running on smartphone technology all your surface tensiometry
(e.g. surface tension and contact angle) needs are met.

Pendant Drop and Surface Drop viewed in Droplet App

Accurate & Precise

With scientifically validated accuracy
and precision,
Dropometer rivals the
most advanced instruments
on the market.


Reap the benefits from
the full connectivity of
your smartphone.
All data can be transferred
to the Cloud, emailed or stored onboard,
and information for measurements
can be derived from the internet.


Dropometer is easily transportable
and suitable for field measurements.
It is battery operated, and light.


The full Dropometer kit consists
of 8 different modules
which can be purchased individually
and put together in various ways
to measure different surface properties.
A budget friendly feature
allowing for buying what you need.


Whether you choose the automatic,
manual or acombination of both versions,
the Dropometer is easy to customize
to suit your diverse needs.

Droplet Lab Video

Surface tension measurement
with a smartphone using a pendant drop

H. Chena,1, Jesus L. Muros-Cobosa,b,1, Juan A. Holgado-Terrizab, A. Amirfazlia,⁎

a Department of Mechanical Engineering, York University, Toronto, ON, M3J 1P3, Canada

b Department of Software Engineering, University of Granada, Granada, 18071, Spain

Received 15 July 2017; Received in revised form 11 August 2017; Accepted 17 August 2017
⁎ Corresponding author.
1 H. Chen and Jesus L. Muros-Cobos contributed equally to this work.
Available online 26 August 2017
0927-7757/ © 2017 Elsevier B.V. All rights reserved.

In this study, a novel powerful mobile surface tension instrument based on a smartphone (mobile-phone or handy) is developed. Axisymmetric drop shape analysis method was implemented on a smart-phone (mobilephone) for surface or interfacial tension measurements. The novelty of this work is that we have been able to implement all the needed calculations on a smartphone, and used the smartphone hardware for image acquisition and display purposes. As such we have been able to create an instrument that is significantly more económica compared to current systems; also it is compact, and can be mobile for field work. It is shown that the accuracy of our method can be 0.001% with ideal synthetic drop profiles (750 synthetic droplets representing a wide range of surface tension values were used). The performance of this instrument was also compared with a high-end commercial surface tension measurement instrument. We used various liquids (from high to low surface tension), and show that our instrument and the developed methodology can provide surface tension measurements as precise and accurate as current commercial instruments.

Flow chart describing the principle of using axisymmetric drop shape analysis method to find the surface tension of liquids. (b) Schematic of the experimental (yellow and theoretical (green) drop profiles.

Contact angle measurement with a smartphone

 H. Chen,1,a)  Jesus L. Muros-Cobos,1,2,a)  and A. Amirfazli1,b)

1Department of Mechanical Engineering, York University, Toronto, Ontario M3J 1P3, Canada

2Department of Software Engineering, University of Granada, Granada 18010, Spain

Published by the American Institute of Physics
(Received 14 January 2018; accepted 3 March 2018; published online 30 March 2018)
AIP Publishing.

In this study, a smartphone-based contact angle measurement instrument was developed. Compared with the traditional measurement instruments, this instrument has the advantage of simplicity, compacto size, and portability. An automatic contact point detection algorithm was developed to allow the instrument to correctly detect the drop contact points. Two different contact angle calcularon methods, Young-Laplace and polynomial fitting methods, were implemented in this instrument. The performance of this instrument was tested first with ideal synthetic drop profiles. It was shown that the accuracy of the new system with ideal synthetic drop profiles can reach 0.01% with both Young- Laplace and polynomial fitting methods. Conducting experiments to measure both static and dynamic (advancing and receding) contact angles with the developed instrument, we found that the smartphonebased instrument can provide accurate and practical measurement results as the traditional commercial instruments. The successful demonstration of use of a smartphone (mobile phone) to conduct contact angle measurement is a significant advancement in the field as it breaks the dominate mold of use of a computer and a bench bound setup for such systems since their appearance in 1980s.