Introducing TAPP X


Launch TAPP X as the world’s most advanced connected mass market water filter in 2020.  

Problem description

Clean drinking water is essential for life on earth. We used to be able to take it for granted but the agriculture and industrial revolutions polluted much of the fresh water sources around the planet. In Europe and North America most governments have taken action to prevent further pollution from happening and clean up contaminated water sources. However, in the United States alone $500 billion are required to upgrade the water infrastructure over the next two decades. Due to lack of investments the problems are likely to get worse.

In Asia, Africa and Latin America the problem is considerably worse with most major cities lacking safe drinking water. Fresh water sources in China, India and Indonesia are currently deteriorating further so this is not likely to improve any time soon.

And not all drinking water issues can be tackled by governments. Many also relate to pipes, leakage and contamination in private buildings and houses. Pipes get replaced over time but e.g. houses built in the 1970s won’t have their pipes replaced until the 2040-2070s based on standard replacement cycles. This means that lead and other contaminants continue to be a serious risk for many homes and families for the foreseeable future.

In addition to this water scientists and health experts are constantly finding new health issues related to drinking water including bi-products from chlorine, micro-plastics, PFAS, radon and many other.

Therefore even if the water provided by the local water supplier is deemed safe to drink at the source it may not be potable at the point of use.

Existing solutions

Home water filters have existed for a long time. The main categories include

  • Water pitchers – just fill it up with water and it filters it for instant use or place in the fridge to keep cool. E.g. Soma and Brita
  • Faucet filters – installs directly on your faucet and usually have a switch to turn filtering on and off. E.g. Tapp Water, Culligan and PUR.
  • Counter top filters – connects to your faucet or standalone to be filled and filters the water for drinking. E.g. Berkey and Propur
  • Under the counter filtration – filters the water specifically for the kitchen with replacement cycles typically every 3 to 12 months. E.g. Culligan and 3M
  • Whole house water filtration system – filters all incoming water in house for kitchen faucets, appliances, bathroom and shower. E.g. PureEffects, 3M, GE, Aquasanaable per market (e.g. bacteria removal, lead removal, limescale removal, etc)
Type of filter Brands Advantages Price
Water Pitcher (Carafe) Brita, Aquasana, PUR, Soma and Amazon Basic (90% market share in Europe and NA) Affordable, easy to install, use and maintain

Improves taste and water quality

From €20 to buy + €5 per cartridge per month (most are more expensive)
Faucet filters Brita, PUR and Culligan (90% market share in Europe and NA) Affordable, easy to install, use and maintain

Improves taste and water quality

From €30 to buy + €6 per cartridge per month (most are more expensive)
Counter top filters Berkey, Mitte and Propur Easy to install, use and maintain

Improves taste and water quality

From €89 to buy + €60 per year for new filters
Fridge filters Electrolux, GE, Whirlpool, Samsung, Bosch (approx 80% market share in Europe and North America) Pre-installed

Improves taste and water quality

Included in price of fridge.

Cost of €100+ to replace per year.

Under the counter filters – Reverse Osmosis Brita, Culligan, APEC, Brondell, iSpring, Home Master (80% market share in Europe and NA) Greater volume and flow than other filters above. Typically €300 or more + installation (€100+) and €100 per year to replace filters

Extra to add back minerals

Under the counter filters – Activated Carbon (and e.g. UV or Ion Exchange) Brita, Culligan, Aquasana (80% market share in Europe and NA) Greater volume and flow than other filters above. Typically €200 or more + installation (€100+) and €80 per year to replace filters
Whole house filters – (e.g. Activated Carbon and Ion Exchange) Aquasana, Home Master, 3M, iSpring APEC, Dupont, Whirlpool All incoming water to the household filtered. Typically €2500+, installation and €500 per year in replacement filters.

Our solution – TAPP X

TAPP X is the first smart connected water filter with mass-market appeal.

The filter can be installed without any tools in less than a minute and start providing clean tasty water and information about the quality of the water before and after.

Short description

  • Faucet water filter based on the core design of TAPP 2 (although shape and functionality may change significantly) that fits on 95% of all household kitchen faucets around the globe and enables filtered and unfiltered water
  • Sensors measuring various attributes of the water before and after including temperature, pH, TDS (total dissolved solvents) and water flow
  • MyTAPP Mobile app + Website that interprets the information and presents it in a customer-friendly format with insights about the water quality, filter status, water consumption (filtered and unfiltered), when to change the filter, eliminated water bottles, CO2 footprint reduction, money saved and more
  • Water filtration cartridges using carbon blocks with 100% organic activated and catalytic carbon for removal of over 100 potential contaminants and 5 other variants of the cartridges including ultrafiltration (removal of bacteria), Ion Exchange (removal of calcium/limescale), UV (removal of bacteria) and nanomembranes (greater removal of e.g. arsenic, radionuclides, pharmaceuticals and more)

What makes TAPP X unique?

  • Connectivity provides real-time data and insights about the tap water
  • Customized filter cartridges depending on the local needs based on the sensor data and other public data
  • Biodegradable cartridges leveraging 4 years of previous research on TAPP 1 and 2  

We are also considering adding a water-saving module that reduces water usage for e.g. doing the dishes by 80%.

Technical Information on TAPP X

Heavy metal & Lead sensor

The sensor developed by Michigan University consists of platinum electrodes for the detection of heavy metal that have a long lifetime. The sensors operate by measuring the impedance change between the electrodes. The four-electrode sensor that can distinguish lead from other heavy metals.

Nitrate Sensor

The YSI nitrate sensor consists of a silver/silver chloride wire electrode in a custom filling solution. The internal solution is separated from the sample medium by a polymer membrane, which selectively interacts with nitrate ions.

pH Sensor

pH sensors are available with tip sizes as small as 10 micrometers with a range of 2-10 pH. Tap water generally has a range of 6-8 with some spread outside this. Resolution is 0.01 pH.

Challenge is finding sensors are short enough for TAPP X. For the early prototypes we’ve used Unisense pH electrode which should match our requirements. This microelectrode is a miniaturized conventional pH electrode based on selective diffusion of protons through pH glass, and the determination of potentials between the internal electrolyte and a reference electrode. 

Water flow sensor and power generating turbine

Currently we’ve experimented with several alternatives for water flow as well as power generation. Ideally we would be able to remove the battery completely and power TAPP X with a turbine. Although we’ve been able to do this in the working prototype, the size of the turbine is still too big for the final version and there is uncertainty about how it will work with low flow and infrequent usage. The flow range that needs to be detected is between 0.1 l/min to 15 l/min with 0.1 l/min resolution.

For water flow we have used two types of components:

  1. a) B.I.O-TECH Ovalgear Flowmeter VZS-007-ALU measuring flow from 50 ml/min to 10 l/min without power generation. The cost is about $5.
  2. b) Yosoo DC Water Turbine Generator Water measuring flow and generating 12V DC with 10W which is enough to power all sensors + bluetooth chip. The cost is about $6.

Both of these are too big for the final version of TAPP X. It’s uncertain if it will be possible to use a turbine to power the filter or if we need to use a battery or a backup battery.

An alternative is to replace the flowmeter with an audio sensor (microphone) to measure the water usage and flow. For the prototype we’ve experimented with CMC-5042PF-AC by CUI Inc. It’s a 100Hz ~ 20kHz Analog Microphone Electret Condenser with a Omnidirectional (-42dB ±3dB @ 94dB SPL) mic. Energy 2V ~ 10V. The cost is $0.55.

Temperature sensor

The temperature sensor is potentially the easiest component to source although flowing water makes it more complicated. For the prototype we use the Microchip Technology MCP9808T. The sensor has a spectrum of -40°C ~ 125°C 10 b 8-DFN (2×3). The cost is about $0.90.

Lead sensor

Initial research shows some lead sensors have been tested in a variety of environments: simulated tap water and water from an actual tap, spiked with metals or not. As lead builds upon the positive electrode, it eventually reaches the neutral electrode, closing the circuit and generating a voltage. Above a one-volt signal, the system registers a hit. The only potential issue found is that copper at high levels can give a false alert.

Other sensors

In parallel with current developers, we are testing new Ion Sensor probes by Libelium that can measure Calcium, Fluoride, Nitrate, Bromide, Chloride, Cupric, Iodide, Silver, Ammonium, Lithium, Magnesium, Nitrite, Percholate, Pottasium and Sodium. The current sensors are too big and energy consumers but are expected to come down in size.

Battery vs turbine / water powered

The vision of TAPP is to provide environmentally friendly products. Therefore we would prefer to avoid having a battery. The challenge with using a turbine however are

  1. TAPP X will rely on the water flow of the faucet which may differ considerably
  2. The size of turbines and accumulator may not be small enough to fit within the TAPP X design
  3. Storing the energy so that TAPP X has enough energy to transmit the energy to a mobile device over bluetooth

We’ve discussed these challenges with Amphiro in Austria who has produced a shower flow meter without battery. One option could be to license this technology which will cost us around $3 to start with.

Alternatively using a battery is still an option as long as instructions about how to recycle it are clear.

Partnerships & Jobs

Tapp Water is actively looking for European partners to support this project including research institutions, suppliers of technology, agencies supporting PR, video creation, events and more.

We are also actively recruiting people for this and other projects including software engineers, hardware designers, data scientists, product managers, marketing managers, quality assurance managers and more.

If you believe you can contribute then please contact us through the contact page.


This project is supported by a grant from the EU H2020 SME program. See for more information.

Want to learn more

Please contact us through the contact page to learn more


October 10, 2018

Written by: Magnus

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