2001 Nextgen, Inc. was established in Jingumae, Shibuya-ku, Tokyo in November, 2001.
2002 Accepted a consulting request from Fusion Communications Corp. (now called Rakuten Communications Corp.), to introduce Sonus G4 and SBC supporting network infrastructures of Japan's first enterprise IP phones. Also brought in SS7RS, Nextgen's original SS7 number translation server.
2004 ・Introduced IP centrex server (now called Cloud PBX) for a major telecommunication carrier.
・Launched Nextgen's solutions NX-E1000, IP-PBX and NX-E1010, SBC for enterprise.
2005 Provided SBC for a major U.S. telecommunication carrier.
2007 ・Listed in the Osaka Securities Exchange "Hercules".
 ‐ SIP based instant messaging and chat system for a major e-commerce company.
 - SIP/VoIP security business and provided a consulting service for a leading telecommunication carrier.
2008 ・Started Nishinihon Branch office in Hiranomachi, Osaka.
・Jointly developed an architecture which separates SIP signal and voice processing, with Acme Packet Inc. USA (now called OracleCorporation) and implemented in Nextgen's NX-B5000 (SBC).
2009 Launched
 - Voice logging solution for enterprise mobile phones.
 - Security consulting system for SIP/VoIP.
2010 ・Launched
 - NXI, the virtual IMS server integrating landline and mobile phone.
 - U³ Live , a cloud-based interactive multimedia service.
・Deployed NX-M1000, M2M connecting server for a machinery manufacturer.
2011 ・Delivered  - NX-E1000, IP-PBX for enterprises for local governments.
 - Test call system for a major telecommunication carrier.
・Released SIP/VoIP Security Audit service for the US telecommunication carrier.
2012 Released a VoIP cloud service called U³ Voice Cloud PBX.
2013 ・Listed on the JASDAQ of the Tokyo Stock Exchange.
・Launched VoIS (now called VoISplus), an enterprise call recording management system over NTT DoCoMo network.
2014 ・Acquired voice logging system business from TEAC CORPORATION.
 - Speech Recognition Voice Mail System for a major telecommunication carrier's call center.
 - Automatic Voice Quality Measuring System for a major telecommunication carrier.
・Moved the head office to Shirogane, Minato-ku, Tokyo.
2015 Introduced IP-STP to a major telecommunication carrier.
2016 ・Relocated Nishinihon branch office to Imabashi, Osaka.
 - VoISplus and LA-6000, software unified call recording solutions.
 - U³ REC, a cloud-based call recording management (voice storage) service.
2017 ・Began capital and business alliance with EXEO Group, Inc. (now called KYOWA EXEO CORPORATION)
・Announced a smartphone-enabled IP-PTT solution (now called NX-PTT) to cover radio dead zones.
・Established Chubu Sales Office in Nagoya, Aichi.
・Systematized enterprise VoIP products and solutions as "VOICEMARK".
・Launched U³ COGNI, a voice-recognition BPO monthly service.
2018 ・Established NextGen Business Solutions, Inc. as a subsidiary and business transferred from neix, Inc.
・Introduced U³ COGNI to SMBC Nikko Securities Inc.
・Launched IVR solution "VOTEX-IVR" with voice recognition function and deployed to a major moving company.
・Established a subsidiary LignApps, Inc.
・Conducted security audits of major European telecommunications carriers with European business partners.
2019 ・Reorganized the enterprise business of the NextGen Group, consolidating part of the business into NextGen Business Solutions, Inc.
・Entered capital and business alliance between subsidiary LignApps, Inc. and NEC Networks & System Integration Corporation.
・Started promoting "MSYS Omnis", a voice recognition service from Marubeni Information Systems Corporation on U³ COGNI.
・Participated in a local 5G verification experiment conducted by SUMITOMO CORPORATION.
・Invested in the U.S. company Telestax, Inc.
・Launched U³ Callback (now called Telework Call.app), an overflow call support service.
・Finalized Capital and business alliance with:
 - EXEO Group, Inc. (previously KYOWA EXEO CORPORATION)
2020 ・Launched
 - Smartphone Extension Solution (now called Telework Call Direct).
 - U³ Callback for Telework (now called Telework Call.app), a solution to telework call-handling issues and offering free of charge for a limited time.
・Started providing local 5G implementation consulting services in collaboration with EXEO Group, Inc.(now called KYOWA EXEO CORPORATION).
・Acquired all shares of subsidiary Acrossway Corporation by LignApps and became a consolidated subsidiary.
・Established Kitanihon branch office in Sapporo, Hokkaido.
・Conducted joint verification of local 5G systems with EXEO Group, Inc. (now called KYOWA EXEO CORPORATION).
・Launched Telework Call.app, a brand name for teleworking solutions for the new normal.
2021 ・Moved Kitanihon branch office from Shiroishi-ku to Toyohira-ku, Sapporo.
・Started providing a local 5G demonstration environment.
・NX-B5000 for Enterprise (SBC) obtained Zoom Phone connection certification (first Japanese product to be certified).
・Launched the U³ Enabler Service, a platform for cloud voice services.
・Delivered mobile core solutions to a major telecommunication company in collaboration with MATRIXX, USA.
・Reached the capital and business alliance with TSUZUKI DENKI CO.,LTD.
・Celebrated Nextgen's 20th anniversary.
2022 ・Launched U³ Friends, an integrated voice communication and connectivity service.
・Merged subsidiary NextGen Business Solutions, Inc. to build a unified organization and to strengthen sales force.
・Signed an agreement with AIESEC Japan Inc. with a mutual understanding to collaborate on the development and provision of a "subtitled telephone service" for the hearing impaired.
・Began demonstration experiment for the full-scale operation of "subtitle phone service" with AIESEC Japan Inc.
・Launched U³ connect, AI-powered call answering services.
・Renamed SaaS brand "U³" to "U-cube" and rebranded as a subscription service brand.
・Merged with subsidiary Acrossway Corporation, consolidating the cloud service planning, development capabilities, operation, and maintenance.
・Formed the capital and business alliance with NEC Networks & System Integration Corporation and IWATSU ELECTRIC CO.,LTD.
2023 ・Created a marketplace to promote and facilitate services through CPaaS, called NextGen CaMP.
・Began a full-scale provision of "U-cube CPaaS," a CPaaS platform utilizing NextGen's own software
・Acquired ISO/IEC 27001:2013 and ISO/IEC 27017:2015 international standards certification for information security management systems (ISMS).